JP2001154549A - Cleaning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To impart press contact force suitable for removing residual toner o the like to a cleaning blade while preventing a foreign matter from being engaged between the cleaning blade and a photosensitive body drum. SOLUTION: This cleaning device is provided with a supporting shaft 14 for freely swingably supporting the cleaning blade 16 for removing the residual toner or the like stuck on the photosensitive body drum and moving in the axial direction of the photosensitive body drum 4 in the state of being integrated with the cleaning blade 16, a press contact member for bringing the cleaning blade 16 into press contact with the photosensitive body drum, an impelling member 21 for urging the supporting shaft 14 to one end part side of the axial direction and a pushing mechanism 23 for intermittently pushing the supporting shaft 14 to the other end part side of the axial direction against the urging force of the impelling member 21. The supporting shaft 14 is provided with a receiving part composed of a flange 22 or the like for receiving the urging force of the impelling member 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device provided with a cleaning blade 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.

[0002]

2. Description of the Related Art Conventionally, as shown in, for example, JP-A-8-146851, a cleaning blade extending in the direction of the center axis of a photosensitive drum (rotary drum) is attached to a blade holder (blade holding member). 2. Description of the Related Art There is known a cleaning device configured to remove a residual toner attached to a peripheral surface of a photosensitive drum by pressing a tip end of a cleaning blade against a peripheral surface of the photosensitive drum.

Further, as shown in FIG. 1, a support shaft 14 for swingably supporting a blade holder 15 on which a cleaning blade 16 is mounted, and the blade holder 15 is swung about the support shaft 14 as a fulcrum. By providing a pressing member 17 composed of a tension spring for pressing the tip of the cleaning blade 16 against the photosensitive drum 4, the tip of the cleaning blade 16 is exposed with a pressing force suitable for removing the residual toner and the like. Pressing against the peripheral surface of the body drum 4 is performed.

[0004] Further, as shown in FIG. 3, an urging member 21 composed of a compression coil spring for urging the blade holder 15 in the axial direction of the support shaft 14, and a urging force of the urging member 21. A push mechanism 23 having a thrust drive gear 24 for intermittently pushing the support shaft 14 in the axial direction is provided. According to the driving force of the push mechanism 23 and the urging force of the urging member 21, By reciprocating the cleaning blade 16 attached to the blade holder 15 in the axial direction of the photosensitive drum 4, foreign matter is prevented from being caught between the cleaning blade 16 and the photosensitive drum 4. Cleaning devices are known.

[0005]

As described above, the urging member 2 composed of the compression coil spring and the driving force of the pushing mechanism 23 is used.
When the cleaning blade 16 is configured to reciprocate in the axial direction of the photosensitive drum 4 in response to the urging force of 1, the damage to the photosensitive drum 4 due to the foreign material biting is effectively prevented. On the other hand, the urging force of the urging member 21 is
Acts as a driving resistance when swinging in a direction in which the cleaning blade 16 is pressed against the photosensitive drum 4, and a rotational force corresponding to a winding direction of a compression coil spring constituting the urging member 21 is applied to the cleaning blade 16. Will be.

Therefore, the swinging displacement of the cleaning blade 16 is hindered by the biasing force of the biasing member 21, and
Despite the provision of the pressing member 17 for pressing the tip of the cleaning blade 16 against the peripheral surface of the photosensitive drum 4, the pressing force of the cleaning blade 16 against the peripheral surface of the photosensitive drum 4 is insufficient due to the insufficient pressing force. There have been problems such as the inability to remove residual toner and the like on the drum 4.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and is capable of preventing foreign matter from being caught between a cleaning blade and a photosensitive drum, and having a pressure contact suitable for removing residual toner and the like. It is an object of the present invention to provide a cleaning device capable of applying a force to the cleaning blade.

[0008]

The invention according to claim 1 is
In a cleaning device provided with a cleaning blade for removing residual toner and the like adhering on a photosensitive drum of an image forming apparatus, the cleaning blade is swingably supported, and the photosensitive drum is integrated with the cleaning blade. A support shaft that moves in the axial direction, a pressing member that presses the cleaning blade against the photosensitive drum, a biasing member that biases the support shaft toward one end in the axial direction, and a biasing force of the biasing member And a pushing mechanism for intermittently pushing the support shaft toward the other end in the axial direction, wherein the support shaft is provided with a receiving portion for receiving the urging force of the urging member. .

According to the above construction, the cleaning blade is reciprocated in the axial direction of the photosensitive drum by intermittently pushing the support shaft in the axial direction in accordance with the driving force of the pushing mechanism. It is possible to effectively prevent foreign matter from being caught between the cleaning blade and the photosensitive drum. And, since the receiving portion for receiving the urging force of the urging member is provided on the support shaft, the urging force of the urging member directly obstructs the swing displacement of the cleaning blade or the direction in which the cleaning blade is rotated. The tip of the cleaning blade is pressed against the photosensitive drum with a pressing force suitable for removing the residual toner and the like in accordance with the urging force of the pressing member.

According to a second aspect of the present invention, in the cleaning apparatus according to the first aspect, the cleaning blade is rotatably supported around a support shaft, and the cleaning blade is moved in the axial direction of the support shaft. The blocking portion for blocking is provided on the support shaft.

According to the above construction, the cleaning blade can be smoothly swung about the support shaft without rotating the support shaft provided with the receiving portion, and the driving force of the pushing mechanism can be changed. The cleaning blade can be reciprocated in the axial direction of the photosensitive drum by intermittently pushing the support shaft in the axial direction in accordance with the above.

[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 this toner image onto a transfer sheet. Charging device 7, developing device 8, transfer roller 9, transfer paper separating claw 10 disposed along the rotation direction
And a cleaning device 1, and an image is scanned and exposed on the photosensitive drum 4 by an exposing device (not shown) to form an electrostatic latent image in an 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 device 8 electrostatically attaches a positively charged toner to a portion of the electrostatic latent image on the photosensitive drum 4 from which a positive charge has been lost by scanning exposure of an image. As a result, the electrostatic latent image on the photosensitive drum 4 is developed with 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 includes a blade holder 15 supported swingably around a support shaft 14 and a blade holder 1.
By applying a pulling force to the cleaning blade 16 attached to the cleaning blade 5 and the base end of the blade holder 15, a pulling force is applied in a direction to press the front end of the cleaning blade 16 against the peripheral surface of the photosensitive drum 4. It has a pressure contact member 17 composed of a coil spring or the like, and a storage section 18 for storing residual toner or the like scraped off from the photosensitive drum 4 by the cleaning blade 16. Note that, instead of the tension coil spring, a pressure contact member made of a compression coil spring, a weight, or the like may be used to press the distal end of the cleaning blade 16 against the peripheral surface of the photosensitive drum 4.

The blade holder 15 is made of a rigid member such as stainless steel, and can be locked on the support shaft 14 by a locking portion 19 such as an E-ring and moved in the axial direction as shown in FIG. By being rotatably supported around the support shaft 14 in the blocked state, it is oscillated about the support shaft 14 as a fulcrum.

The support shaft 14 is supported by a bearing 20 so as to be slidable in the axial direction, and is urged toward one end in the axial direction by an urging member 21 composed of a compression coil spring or the like. That is, the support shaft 14 is provided with a flange 22 serving as a receiving portion for the urging member 21, and the urging member 21 is disposed between the flange 22 and the bearing 20. By applying the pressing force of the urging member 21 to the flange 22, the support shaft 1
4 is configured to be biased toward one end thereof.

The support shaft 14 is intermittently pushed toward the other end in the axial direction by a pushing mechanism 23 provided at one end thereof against the urging force of the urging member 21. It is configured to be. The pushing mechanism 23 has a thrust drive gear 24 having at least one side wall surface 25 formed into a tapered surface, and the rotation center 26 is disposed at a position offset by a predetermined distance from the support shaft 14. In addition, the side wall surface 25 of the thrust drive gear 24 is disposed in a state of contacting one end of the support shaft 14.

The thrust drive gear 24 is rotated by a drive mechanism (not shown) from a state shown by a solid line to a state shown by a virtual line in FIG. From the state where the support shaft 14 is pushed toward the other end in the axial direction, as shown by the phantom line in FIG. The support shaft 14 is reciprocated in the axial direction by being displaced to a state where the support shaft 14 is pushed back.

The amount of movement of the support shaft 14 can be set to various values according to the inclination angle of the side wall 25 of the thrust drive gear 24, but is generally set to about 1 to 2 mm. The support shaft 14 is intermittently pushed to the other end side against the urging force of the urging member 21 by an actuator such as a driving cam or a push-pull solenoid instead of the thrust driving gear 24. May be configured.

The cleaning blade 16 is made of an elastic material such as polyurethane rubber, and is attached to the mounting portion of the blade holder 15 by means of bolting or bonding. As a result, the photosensitive drum 4 is moved in the axial direction while being integrated with the support shaft 14 and the blade holder 15. The leading end of the cleaning blade 16 is pressed against the peripheral surface of the photosensitive drum 4 by a predetermined pressing force by the pressing member 17, so that residual toner or paper dust adhered to the peripheral surface of the photosensitive drum 4. Are scraped off and removed.

As described above, the cleaning blade 16 is swingably supported, and the supporting shaft 14 that moves in the axial direction of the photosensitive drum 4 integrally with the cleaning blade 16, and the cleaning blade 16 is attached to the photosensitive drum 4. A urging member 21 for urging the support shaft 14 toward one end in the axial direction; and a urging member 21 for urging the support shaft 14 in the other axial direction against the urging force of the urging member 21. A pushing mechanism 23 for intermittently pushing the end portion side, and the flange 2 receiving the urging force of the urging member 21 on the support shaft 14
2, the urging force of the urging member 21 is applied to the support of the cleaning blade 16, that is, the blade holder 15, as in the conventional device configured to act on the blade holder 15. It is possible to prevent the swinging displacement of the cleaning blade 16 from being hindered by the urging force and prevent the cleaning blade 16 from being given a rotational force.

Therefore, by always pressing the tip of the cleaning blade 16 against the photosensitive drum 4 with an appropriate pressing force by the pressing member 17, the residual toner and the like on the photosensitive drum 4 can be reliably removed. And the driving force of the pushing mechanism 23 and the urging member 21
The cleaning blade 16 is reciprocated in the axial direction of the photosensitive drum 4 together with the support shaft 14 in accordance with the urging force of the above, thereby preventing foreign matter from being caught between the cleaning blade 16 and the photosensitive drum 4. Thus, it is possible to effectively prevent the situation where the surface of the photosensitive drum 4 is damaged.

In the case where the cleaning blade 16 is rotatably supported around the support shaft 14 as shown in the above embodiment, the cleaning blade 16 is provided without rotating the support shaft 14 provided with the flange 22. The cleaning blade 16 can be smoothly swung about the support shaft 14. Further, a locking portion 19 such as an E-ring for preventing the blade holder 15 from moving in the axial direction of the support shaft 14 is provided.
4 is intermittently pushed in the axial direction, so that the cleaning blade 16 is moved together with the blade holder 15.
Can be reciprocated in the axial direction of the photosensitive drum 4. Therefore, without being affected by the urging force of the urging member 21, the cleaning blade 16 is smoothly oscillated by the urging force of the pressing member 17, and the leading end of the cleaning blade 16 is appropriately pressed against the photosensitive drum 4. Can be pressed.

In the above embodiment, an example was described in which the cleaning blade 16 was attached to the blade holder 15 and the cleaning blade 16 was supported on the support shaft 14 via the blade holder 15. The cleaning blade 16 may be directly supported on the shaft 14.

Further, instead of the above-described embodiment in which the cleaning blade 16 is rotatably supported around the support shaft 14, the blade holder 15 is integrally fixed to the support shaft 14, so that the cleaning blade 16 is fixed together with the support shaft 14. The cleaning blade 16 may be configured to move in the axial direction of the photosensitive drum 4. In this case, the support shaft 1
4, the cleaning blade 16 is not affected by the urging force of the urging member 21 and is supported by the cleaning blade 16 according to the urging force of the pressing member 17 by rotatably supporting a collar serving as a receiving portion of the urging member 21. Is preferably configured to smoothly oscillate.

[0030]

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. A support shaft that supports and moves in the axial direction of the photoconductor drum in an integrated state with the cleaning blade, a pressing member that presses the cleaning blade against the photoconductor drum,
An urging member for urging the support shaft toward one end in the axial direction;
A pushing mechanism for intermittently pushing the support shaft toward the other end in the axial direction against the biasing force of the biasing member, wherein the support shaft receives the biasing force of the biasing member. Because the part was provided,
As in the conventional device configured to directly apply the urging force of the urging member to the cleaning blade, a situation in which the swing displacement of the cleaning blade is hindered or a rotational force is applied to the cleaning blade. By causing the tip of the cleaning blade to always press the photosensitive drum against the photosensitive drum with an appropriate pressing force by the pressing member, the residual toner and the like on the photosensitive drum can be reliably removed, and the pressing Foreign matter bites between the cleaning blade and the photosensitive drum by reciprocating the cleaning blade along with the support shaft in the axial direction of the photosensitive drum in accordance with the driving force of the mechanism and the urging force of the urging member. This is advantageous in that it can be effectively prevented.

[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 a diagram corresponding to FIG. 2, showing a conventional example of a cleaning device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cleaning device 4 Photoreceptor drum 16 Cleaning blade 17 Pressure contact member 19 Locking part 21 Biasing member 22 Flange (receiving part) 23 Pushing mechanism

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Keisuke Oba 1-2-2 Tamazo, Chuo-ku, Osaka Mita Kogyo Co., Ltd. F-term (reference) 2H034 BF06 BF08 BF10

Claims (2)

[Claims] 1. A cleaning device having a cleaning blade for removing residual toner and the like adhering on a photosensitive drum of an image forming apparatus, wherein the cleaning blade is swingably supported and is integrated with the cleaning blade. A supporting member that moves in the axial direction of the photosensitive drum, a pressing member that presses the cleaning blade against the photosensitive drum, an urging member that urges the supporting shaft toward one end in the axial direction, A pushing mechanism for intermittently pushing the support shaft toward the other end in the axial direction against the urging force of the urging member, wherein the support shaft receives a urging force of the urging member. A cleaning device, comprising: 2. The cleaning device according to claim 1, wherein the locking portion rotatably supports the cleaning blade around a support shaft, and the locking portion for preventing the cleaning blade from moving in the axial direction of the support shaft. A cleaning device provided on a support shaft.