JPH0670731B2 - Cleaning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is applied to an image forming apparatus such as an electrophotographic copying machine / microdevice or a laser beam printer. The present invention relates to a cleaning device that abuts and removes a blade member.

[Prior Art] A cleaning device for removing toner from a photoconductor of an electrophotographic copying machine will be described below as an example.

In an electrophotographic copying machine adopting an electrophotographic system, in which a toner image is formed on a photoconductive photoconductor and then the toner image is transferred onto a copy sheet, after the toner image is transferred, the residual toner remains on the surface of the photoconductor. It is necessary to remove the toner and prepare for the next transfer step. Therefore, a cleaning device is usually provided to remove the residual toner. Therefore, as a cleaning device, conventionally, a plate-like cleaning blade is brought into contact with the surface of the photoconductor to remove the residual toner adhering to the surface of the photoconductor.

[Problems to be solved by the invention]

However, when the toner is removed from the surface of the photoconductor with the cleaning blade, a part of the toner removed from the surface of the photoconductor remains without being separated from the surface including the toner removal edge of the blade (the lower end surface of the blade). Then, the toner remaining on the lower end face of the blade receives a force of moving toward both ends in the blade longitudinal direction due to the movement of the photosensitive member, and finally scatters from both ends of the blade and scatters to the outside of the cleaning device.

In order to prevent the toner scattering, it has been proposed to attach a seal member such as a sponge to both ends of the blade.

However, it was found that the toner scattered from both ends of the blade is scattered from the entire thickness portion of both ends of the blade.
Therefore, in order to prevent toner scattering, a larger seal member is required as the thickness of both ends of the blade is larger.

[Object of the Invention]

Therefore, an object of the present invention is to solve the above-mentioned problems and to provide a cleaning device capable of removing an adhered matter such as toner adhered to a surface to be cleaned in a state where the scattering thereof is small. is there.

The present invention to achieve this object, in a cleaning device for removing residual toner from the image bearing member, having a cleaning blade that contacts the image bearing member along the longitudinal direction of the image bearing member, It is characterized in that it has thin-walled portions, which are formed by cutting out an edge on the side opposite to the edge abutting on the carrier, on both outer sides of the effective cleaning width in the blade longitudinal direction.

〔Example〕

1 and 2 are side views showing an embodiment according to the present invention.

In the figure, a holder 4 that rotates around a rotary shaft 5
Is urged counterclockwise in FIG. 1 by a spring 8, and a holder 6 is rotatably attached to the holder 4 around a rotation shaft 7. Also,
A plate-like cleaning blade 3 (hereinafter referred to as a blade) for wiping off the residual toner on the surface 2 of the photoconductor 1 is supported by the holder 6 and contacts the surface 2 of the photoconductor. The edge 3a of the blade 3 comes into contact with the above-mentioned two shafts 5
-Because it is supported by the holder 6 which is rotatable around 7, it is even over the entire length of the edge 3a. Therefore, this blade supporting method can obtain a uniform contact state of the blade over the entire surface of the photoconductor as compared with the fixed supporting method. Further, 9 is an auxiliary roller made of silicon rubber, which has a role of improving the recovery efficiency of the residual toner, and is in contact with the surface of the photoconductor 2 at a desired pressure so as to be higher or lower than the moving speed of the surface of the photoconductor 2. By rotating, a sufficient rubbing force is obtained, and it also has a function of removing miscellaneous deposits such as paper dust other than the residual toner on the surface of the photoconductor 2 which causes image deterioration.

Now, after the transfer, the residual toner remaining on the surface 2 of the photoconductor passes between the photoconductor drum 1 and the auxiliary roller 9 which rotates in the forward direction, and reaches the edge portion 3a of the blade 3, This edge action releases the photoconductor surface 2.

Further, the residual toner of the connection is also continuously transferred to the edge portion 3a.
Can be released, and gradually accumulate in the valley formed by the lower end face 3b of the blade 3 and the photoconductor surface 2 over the width of the image forming area. Then, when it accumulates to a certain extent, it drops and adheres to the surface of the auxiliary roller 9, moves to the waste toner house side 12 together with the surface of the rotating auxiliary roller 9, and is scraped off by the scraper 10 that contacts the surface of the auxiliary roller 9. It is collected in the waste toner house 12.

In this cleaner, end seals 13 made of felt material or the like are provided outside both ends of the blade so that the toner scattered from the lower ridges 3a on both end surfaces of the blade 3 does not escape to the outside of the cleaner as much as possible. It is provided. In this cleaner, since the blade supporting system is the so-called equalizing system, the end seal 13 and the blade end face are not brought into close contact with each other and have a slight gap (about 1 mm).

Now, as shown in the perspective view of FIG. 3, the blade 3 in the present embodiment is outside the effective width of the cooling, and is a non-contact side of the photosensitive member surface 2 at both end portions in the longitudinal direction, that is, Part of the meat on the side that is not the edge that abuts on the surface 2 of the photoconductor is cut into a triangular prism shape. That is, the notches 15 are provided at both corners of both ends thereof. Therefore, the width of the lower end face of the present blade 3 at both end portions is narrowed to about 1/3 to 1/4 as compared with the central portion in the longitudinal direction. Therefore, even if the toner removed from the photoconductor surface 2 in the image area width X and deposited on the blade lower end surface 3b moves toward both ends of the blade along the valley formed by the blade 3 and the photoconductor surface 2, The toner of about 2/3 drops into the container at the position of the distance D (FIG. 3) from the end of the blade, and the toner reaching the end of the blade is only the toner having the thickness F. Therefore, a very small seal member for preventing toner scattered from both ends of the blade is sufficient.

Although the problem of toner scattering is greatly improved only in the above-described embodiment, it is found that the toner used in this embodiment is a magnetic toner, and in addition to this, the magnet roller 14 is further provided. Is getting a bigger effect. As shown in FIG. 2, magnet rollers 14 are arranged at both ends of the auxiliary roller 9 (however, only one end thereof is shown in the figure), and the magnetic toner that drops and scatters on the peripheral surface of the magnet roller 14 by magnetic force. It attracts and captures. Since the magnet roller 14 is arranged so as not to be in close contact with the photosensitive member surface 2 with a gap and is rotated, when it is arranged on the same axis 16 as the auxiliary roller 9 as in this embodiment, the diameter is Is smaller than the auxiliary roller 9, and the position and length in the axial direction where it is arranged avoids the image forming area,
Further, it extends over at least the region of the blade 3 facing the portion 15 where the end face width of the tip portion is small. Further, like the auxiliary roller 9, the scraper 10a is in contact with the peripheral surface of the magnet roller 14, and the toner attached to the surface of the rotating magnet roller 14 is scraped off by the scraper 10a. Will be recovered in.
It should be noted that a rubber magnet or the like may be used instead of the magnet roller 14 to have a sufficient effect, but the larger the surface magnetic flux, the larger the effect.

As described above, in this embodiment, at least the end portion 15 of the cleaning blade 3 has a small end surface width 15
And a magnet roller 14 which is provided substantially in parallel with the cleaning blade 3 across the opposing area and which is arranged with a desired gap therebetween and rotates in the forward direction with respect to the moving direction of the photoconductor surface 2. And a scraper 10a that abuts against.

Next, an example of the effect of using this embodiment will be shown.

With the shape of the blade 3 shown in FIG. 3, the image area width X is 297 mm.
In the case of, the vertical length A is 330 mm, the horizontal length B is 20 mm, the thickness is 2 mm, the length E of one side of the notch is 5 mm, and the length D of the other side is
11mm, the thickness F of the thin portion of the cutout blade is 0.5mm,
When a blade having a distance G from the edge of the image area to the thin portion of 5.5 mm was used for cleaning the photoconductor, an experiment was conducted, and conventionally, 10,000 to 20,000 times of images were produced, and noticeable peripheral dirt was almost noticeable. In addition, a great effect was obtained against the dirt of the charging wire, and the cleaning of the wire became unnecessary for a long time. The effective cleaning width of the blade is at least equal to or larger than the image area width of the photoconductor.

Still another embodiment will be described.

In the above embodiment, the cutting shape of the blade is shown as a triangular prism, but still another embodiment will be shown below.

In FIG. 4, rectangular notch portions 20 are provided at both ends outside the effective cleaning width of the blade 3, and thick-walled portions 21 thinner than the effective cleaning width are provided at both ends of the blade.

In FIG. 5, curved notches 22 are provided at both ends outside the effective cleaning width of the blade 3, and a thick portion 23 thinner than the effective cleaning width is provided at both ends of the blade. .

In FIG. 6, triangular pyramidal notches 24 are provided at both ends outside the effective cleaning width of the blade 3, and a thick portion 25 thinner than the effective cleaning width is provided at both ends of the blade.
Is provided.

In FIG. 7, laterally long triangular notches 26 are provided at both ends outside the effective cleaning width of the blade 3, and a thick portion 27 thinner than the effective cleaning width is provided at both ends of the blade. It is a thing.

FIG. 8 shows that the blade 3 is provided with slopes b and c that gradually descend from the widthwise central portion a toward both end portions, that is, the blade thickness is gradually reduced. Also in this example, outside the effective cleaning width of the blade, a portion 26 where the end face width is thinner than the thickness of the effective width.
27 are provided. Then, the adhered substances such as toner and paper dust removed from the surface of the photoconductor are inclined as shown by the arrow b.
It gradually moves to the blade end along c, but as the thickness of the blade becomes thinner, the amount of deposits decreases, and the scattering of deposits from the blade end decreases.

Still another embodiment is shown in FIGS. 9 and 10.

In this embodiment, a recess 28 or a recess 29 is provided outside the effective cleaning width of the blade 3 and slightly inside the side end of the blade 3 (in this case, about 5 mm inside). . The recess 28 has a rectangular parallelepiped shape, and the recess 29 has a curved shape. In the case of this example, the deposits that have fallen into the recesses 28 and 29 are the inner ends 30 and 31 of the blade (the ends of the recesses 28 and 29).
Further, the movement of the blade toward the end portion of the blade is restricted, so that the scattering of deposits is also reduced.

In the above-described embodiment, since the blade 3 is rotatably supported, the end seal 13 is not in close contact with the blade and has a gap (about 1 mm) between the end of the blade and the present invention is particularly effective. However, the same excellent effect can be obtained also in a cleaning device in which the blade 3 is fixedly supported and provided with a contact type end seal that comes into contact with the blade. Further, in the present embodiment, the cleaning device in which the auxiliary roller 9 is arranged so as to face the blade 3 over the image forming area has been described as an example, but the surface to be cleaned faces the blade over the image forming area. Of course, the present invention can be applied to a cleaning device provided with a scooping sheet that abuts against. The surface to be cleaned is a surface of an image carrier such as a photoconductor or an insulator for forming an image, the surface of a fixing roller, the surface of a transfer roller, or the like, to which toner, paper dust, or the like adheres. .

〔The invention's effect〕

As described above, according to the present invention, since the residual toner is cleaned by the cleaning blades having the thin portions notched at the edge on the side opposite to the edge abutting the image bearing member at both ends in the longitudinal direction of the image bearing member, There is an effect that the residual toner scattering area can be narrowed, and the scattering prevention treatment by a toner scattering prevention member such as an end seal can be easily performed.

[Brief description of drawings]

FIG. 1 is a side view of a cleaning device to which an embodiment of the present invention is applied, FIG. 2 is a perspective view of an essential part thereof, and FIGS. 3 to 10 are perspective views of an essential part of a blade applied to the present invention. is there. In the figure, 2 ... Photoconductor surface, 3 ... Cleaning blade, 9 ... Auxiliary roller, 10, 10a ... Scraper, 1
2 …… Exhaust toner house, 13 …… End seal, 14 …… Magnet roller, 15 ・ 20 ・ 22 ・ 24 ・ 26 …… Notch part, 21 ・
23 ・ 25 ・ 27 …… The thin, thick part of the blade.

Claims (1)

[Claims] 1. A cleaning device for removing residual toner from an image carrier, comprising a cleaning blade that contacts the image carrier along the longitudinal direction of the image carrier, wherein the cleaning blade contacts the image carrier. A cleaning device comprising: a thin-walled portion, which is formed by cutting out an edge on the side opposite to the edge in contact, on both outer sides of the effective cleaning width in the blade longitudinal direction.