JP2001249591A - Cleaning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the uneven wear of a photoreceptor drum while preventing the pass-through of residual toner or the like. SOLUTION: In a cleaning device provided with a cleaning blade 17 to remove the residual toner or the like stuck on the photoreceptor drum of an image forming device, the cleaning blade 17 is supported by a blade supporting part 22 provided at a blade holder 16, and sealing members 19 to seal both right and left side end parts of the cleaning blade 17 are provided, and the projecting measure of the cleaning blade 17 is set so that both right and left side end parts of the cleaning blade 17 are largely projected from the blade supporting part 22 as compared with a center part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus provided with a cleaning blade made of an elastic member for removing residual toner and the like adhered on a photosensitive drum of an image forming apparatus such as a copying machine or a laser beam printer. It is.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Unexamined Patent Publication No. Hei.
As shown in the publication, a cleaning blade extending in the direction of the center axis of the rotating drum (photosensitive drum) is attached to a blade holding member (blade holder), and the leading end of the cleaning blade is pressed against the peripheral surface of the rotating drum. There is known a cleaning device configured to remove residual toner attached to the peripheral surface of a rotating drum by performing the cleaning.

Further, as shown in FIG. 4, the residual toner and the like removed from the photosensitive drum by the cleaning blade 17 are prevented from slipping through the side end of the cleaning blade 17 and leaking out of the cleaning device. Therefore, a sealing member 19 made of urethane foam or the like is formed so as to cover the back surfaces of both left and right end portions of the cleaning blade 17.
Has been established.

[0004]

As described above, the seal members 19 are provided on the back surfaces of the left and right end portions of the cleaning blade 17 as described above.
When the cleaning blade 17 is configured so as to prevent the residual toner or the like from slipping through, the left and right end portions of the cleaning blade 17 are supported by the seal member 19 and deformation thereof is suppressed. The left and right ends are firmly pressed against the photosensitive drum. As a result, there is a problem that the photosensitive drum is unevenly worn and image unevenness is likely to occur, and the life of the photosensitive drum is shortened.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a cleaning device capable of preventing uneven wear of a photosensitive drum while preventing residual toner and the like from slipping through.

[0006]

The invention according to claim 1 is
In a cleaning device including a cleaning blade for removing residual toner and the like attached to a photoreceptor drum of an image forming apparatus, the cleaning blade is supported by a blade supporting portion provided on a blade holder, and the left and right sides of the cleaning blade A sealing member for sealing an end portion is provided, and the projecting dimension of the cleaning blade is set such that both left and right end portions of the cleaning blade project more from the blade support portion than the central portion.

[0007] According to the above configuration, the left and right ends of the cleaning blade are supported by the sealing member, and the shape retention force of the left and right sides of the blade by the blade supporting portion of the blade holder is smaller than that of the central portion. In addition, by setting the dimension of the cleaning blade projecting from the blade support portion, the pressing force of the cleaning blade against the photosensitive drum is set uniformly, thereby preventing uneven wear of the photosensitive drum.

According to a second aspect of the present invention, in the cleaning device according to the first aspect, the protrusion dimension of the cleaning blade is gradually increased toward both left and right end portions.

According to the above configuration, the protrusion dimension of the cleaning blade from the blade support portion of the blade holder gradually increases toward the left and right end portions, so that the cleaning blade is held by the blade support portion of the blade holder. A sudden change in the forming force in the longitudinal direction of the blade is prevented.

According to a third aspect of the present invention, in the cleaning device according to the first or second aspect, the protrusion dimension of the cleaning blade at both left and right end portions of the blade supporting portion is 1.1 to 2.0 times the central portion. Is set within the range of.

[0011] According to the above configuration, the projecting dimension of the cleaning blade is set such that the shape retaining force of the left and right side edges of the blade by the blade support portion of the blade holder is appropriately smaller than the central portion. Thus, the pressing force of the cleaning blade against the photosensitive drum is set uniformly.

[0012]

FIG. 1 shows a main part of an image forming apparatus provided with a cleaning device 1 according to an embodiment of the present invention. This image forming apparatus includes a sheet transport unit 3 having a registration roller 2, an image forming unit 5 having a photosensitive drum 4, and a fixing unit 6 disposed downstream of the image forming unit 5 in the sheet transport direction. And

The image forming section 5 forms a predetermined toner image on the photosensitive drum 4 by an electrophotographic process, and transfers the formed toner image onto transfer paper.
, A charging device 7, a developing device 8, a transfer roller 9, a transfer paper separating claw 10, and a cleaning device 1 disposed along the rotation direction of the photosensitive drum 4. The original image is scanned and exposed to form an electrostatic latent image in the image area.

The charger 7 includes a charging wire (not shown) to which a high voltage is applied. The charging wire 7 performs, for example, a positive corona discharge to thereby charge the photosensitive drum 4.
Is charged to a predetermined positive potential.

The developing unit 8 electrostatically attaches the positively charged toner to the portion of the electrostatic latent image on the photosensitive drum 4 from which the positive charge has been lost due to the scanning exposure of the original image. . Thus, the electrostatic latent image on the photosensitive drum 4 is developed by the toner, and a toner image is formed on the surface of the photosensitive drum 4 as a visible image.

The transfer roller 9 is disposed opposite to the photosensitive drum 4 in a non-contact state, and is formed on the photosensitive drum 4 by performing a negative corona discharge from the back side of the transfer paper. The toner image is electrostatically transferred onto a transfer sheet.

The fixing unit 6 includes a heating roller 12 for heating the transfer sheet on which the toner image has been transferred in the image forming unit 5.
And a pressure roller 13 that presses the transfer sheet against the heating roller 12 to fuse and fix the toner image on the transfer sheet.

The cleaning device 1 provided in the image forming section 5 is mounted on a mounting bracket 15 swingably supported by a support shaft 14 as a fulcrum, and is fixed to the mounting bracket 15 by means such as bolting. Blade holder 16
The cleaning blade 17 fixed to the blade holder 16 and the pulling force for urging the distal end of the cleaning blade 17 in the direction of pressing the peripheral surface of the photosensitive drum 4 by pulling the base end of the mounting bracket 15. The cleaning blade 17 includes a spring 18, a sealing member 19 for sealing a side end of the cleaning blade 17, and a storage unit 20 for storing residual toner or the like scraped off from the photosensitive drum 4 by the cleaning blade 17.

The blade holder 16 is made of a rigid member such as stainless steel, and includes a fixing portion 21 fixed to the mounting bracket 15 and a blade supporting portion 22 extending in a direction perpendicular to the fixing portion 21. The base end (upper end) of the cleaning blade 17 is fixed to the front surface of the blade support section 22 by means such as bolting or bonding.

As shown in FIG. 2, the blade support 22 is dimensioned such that both left and right ends of the cleaning blade 17 protrude more from the blade support 22 than the center. That is, since the tip edge of the blade support portion 22 is formed in an arch shape, the protrusion dimension W2 of the left and right end portions of the blade is set to be larger than the protrusion dimension W1 of the central portion. As a result, the tip (lower end) of the cleaning blade 17 extending horizontally from the tip edge of the blade support 22.
Projecting dimension is minimum at the center of the blade and gradually increases toward the left and right ends.

The cleaning blade 17 is made of an elastic member such as polyurethane rubber and the like.
By pressing the tip against the peripheral surface of the photosensitive drum 4 with a pressing force corresponding to the urging force of 8, the residual toner or paper dust adhered to the peripheral surface of the photosensitive drum 4 is scraped and removed. Things.

The sealing member 19 is made of polyurethane foam or the like.
1 is extended along the back surface of the left and right side portions of the left and right sides, that is, downwardly in FIG. 1, so that residual toner and the like scraped off by the cleaning blade 17 It is configured to prevent the toner from leaking out of the cleaning device 1 through the section.

By providing the seal member 19 for restricting the lateral movement of the residual toner or the like removed from the photosensitive drum 4 by the cleaning blade 17 as described above, the residual toner or the like is prevented from slipping through the housing portion 20.
In the cleaning device 1 configured to be collected inside the cleaning blade 17, the protrusion dimension of the cleaning blade 17 is set such that both left and right end portions of the cleaning blade 17 protrude more from the blade support portion 22 than the center portion. Therefore, despite the provision of the seal members 19 at both left and right end portions of the cleaning blade 17,
By setting the pressure contact force to the photosensitive drum 4 uniformly, uneven wear of the photosensitive drum 4 can be effectively prevented.

That is, when the seal members 19 are provided so as to cover the left and right ends of the cleaning blade 17, the left and right ends of the cleaning blade 17 are reinforced by the seal members 19, so that the left and right ends are reinforced. Deformation of both side ends is suppressed, and the pressing force on the photosensitive drum 4 tends to increase. In response to this, when the protrusion dimension of the cleaning blade 17 from the blade support portion 22 is set as described above, the effect of suppressing the deformation of the left and right side edges of the blade by the blade support portion 22 is reduced. The pressing force of the right and left ends of the blade against the drum 4 can be relatively reduced. For this reason, the cleaning blade 1 by the seal member 19 is used.
7 and the pressing force on the photosensitive drum 4 determined by the sum of the shape retaining force of the cleaning blade 17 by the blade supporting portion 22 and the pressure contact force on the photosensitive drum 4 are set substantially uniformly over the entire length thereof. Uneven wear can be prevented.

Therefore, a part (left and right ends) of the cleaning blade 17 is firmly pressed against the photosensitive drum 4 without impairing the effect of preventing the residual toner from slipping off by providing the seal member 19, and the peripheral surface thereof is Can be effectively prevented from being unevenly worn, the occurrence of image unevenness due to the uneven wear can be suppressed, and the life of the photosensitive drum 4 can be prolonged.

Further, as shown in the above embodiment, by forming the tip edge of the blade supporting portion 22 in an arch shape, the cleaning blade 1 from the blade supporting portion 22 is formed.
In the case where the projecting dimension of 7 is gradually increased from the central portion to the left and right end portions, the blade holding force of the blade support portion 22 does not suddenly change in the longitudinal direction. It is possible to effectively prevent uneven wear of the photosensitive drum 4 due to a sudden change in the pressure of the cleaning blade 17 against the photosensitive drum 4. In addition, even when the protrusion dimensions at both left and right end portions of the cleaning blade 17 are set to be significantly larger than those at the center portion, there is an advantage that the sudden change in the pressing force can be prevented.

In addition, instead of the above-described embodiment in which the tip edge of the blade support portion 22 is formed in an arch shape, the tip edge of the blade support portion 22 is formed in a tapered shape, so that the cleaning blade 17 protrudes. The size may be configured to gradually increase linearly as it reaches the left and right end portions. Alternatively, as shown in FIG. 3, a notch 30 corresponding to the installation range of the seal member 19 may be formed in the blade support portion. By forming them on both left and right ends of the cleaning blade 22, the protrusion dimensions of the left and right both ends of the cleaning blade 17 may be set to be larger than those of the central part.

The ratio of the protrusion dimension W2 of the cleaning blade 17 at the left and right ends of the blade support portion 22 to the protrusion dimension W1 of the central portion depends on the material of the cleaning blade 17, the plate pressure, the strength of the seal member 19 and the like. Depending on the value can be set to various values, but if the ratio is too small, the effect of reducing the shape retention force of the left and right side edges of the blade is insufficient, and conversely, if the ratio is too large,
The effect of reducing the shape-retaining force is excessive, and the pressing force of the left and right end portions of the blade against the photosensitive drum 4 becomes too small. Therefore, in order to effectively prevent uneven wear of the photosensitive drum 4 while setting the shape retaining force of the cleaning blade 17 to an appropriate value, the blade support portion 22 is required.
It is preferable to set the protruding dimension of the cleaning blade 17 at both left and right end portions within a range of 1.1 to 2.0 times the central portion.

[0029]

As described above, the present invention relates to a cleaning apparatus provided with a cleaning blade for removing residual toner and the like adhering on a photosensitive drum of an image forming apparatus. And a sealing member for sealing the left and right side edges of the cleaning blade, and the left and right side edges of the cleaning blade protrude more from the blade support portion than the center portion. Since the protrusion dimension of the cleaning blade is set, the left and right end portions of the cleaning blade are firmly pressed against the photosensitive drum without impairing the effect of preventing the residual toner from slipping off by providing the seal member, and the peripheral surface thereof is uneven. Effectively prevent wear,
There is an advantage that the occurrence of image unevenness due to uneven wear can be suppressed and the life of the photosensitive drum can be extended.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a main configuration of an image forming apparatus provided with a cleaning device according to the present invention.

FIG. 2 is an explanatory diagram illustrating a main configuration of a cleaning device according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating a main configuration of a cleaning device according to another embodiment of the present invention.

FIG. 4 is an explanatory view showing a conventional example of a cleaning device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cleaning device 4 Photoconductor drum 16 Blade holder 17 Cleaning blade 22 Blade support part 19 Seal member

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Eiji Tatsumi, Inventor 1-2-28 Tamazo, Chuo-ku, Osaka-shi F-term in Kyocera Mita Corporation (reference) 2H034 BF01 BF03 BF03

Claims (3)

[Claims] An image forming apparatus including a cleaning blade for removing residual toner and the like adhering on a photosensitive drum, wherein the cleaning blade is supported by a blade supporting portion provided on a blade holder; Sealing members for sealing both left and right ends of the cleaning blade are provided, and the protrusion dimensions of the cleaning blade are set so that the left and right ends of the cleaning blade protrude more from the blade support portion than the central portion. And a cleaning device. 2. The cleaning device according to claim 1, wherein a protrusion dimension of the cleaning blade is gradually increased toward both left and right end portions. 3. The cleaning device according to claim 1, wherein the protrusion dimensions of the cleaning blade at both left and right end portions of the blade support portion are 1.1 to 1.1 at a central portion.
A cleaning device, wherein the cleaning device is set within a range of 2.0 times.