JPH10239931A - Cleaning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a deterioration in a cleaner blade and the surface of a photoreceptor caused by ozone and heat by hardly making the ozone and heat close. SOLUTION: Ozone air generated in an electrifier 2 is made to flow to the side of a blade holder 3b, to be discharged outside, together with the sucking of outdoor air from the surroundings, through openings 2d, 3c and 3d provided in the blade holder 3b of the cleaner blade 3a for cleaning the surface of an image carrier 1 and the upstream side wall 2b1 in the rotational direction of the image carrier 1, of the electrifier 2 located in the vicinity of the blade holder 3b. Thus, ventilation and cooling are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrophotographic copying machine,
The present invention relates to a cleaning device for cleaning an image carrier provided in a common image forming unit of an image forming apparatus that forms an image by an electrophotographic method such as an electrophotographic printer and an electrophotographic facsimile.

[0002]

2. Description of the Related Art If the accuracy of mounting a cleaner blade, a charger, and a static elimination sheet to an image carrier is poor, poor cleaning, poor charging, and poor static elimination may occur. In order to cope with this, each of them is positioned and mounted with high precision.

Further, there are a charger and an optical eraser near the cleaner blade. If ozone generated by the charger or heat generated by the optical eraser remains near the cleaner blade, there is a problem that the cleaning blade and the charge removing sheet are deteriorated, and the surface of the image carrier is deteriorated, thereby causing image noise.

Japanese Unexamined Patent Publication No. Hei 3-15864 discloses a structure in which a charger and a blade cleaner or a fab brush cleaner are integrally formed. This arrangement can easily obtain the positioning accuracy as compared to the case where the charger and the cleaner blade or the brush are individually positioned and mounted, since the mutual positioning is uniquely performed.

Japanese Patent Application Laid-Open No. Sho 61-213870 discloses that a wind discharge wall capable of discharging air is provided on a part of a shield member of a charger, and ozone in the shield member is charged from the back of the shield member. A device provided with ventilation means for forced ventilation toward the surface of the photoreceptor is disclosed. In this case, the ozone can be discharged from the shield member of the charger to prevent ozone from remaining in the shield member and adversely affecting the surface of the photoconductor.

[0006]

However, Japanese Patent Application Laid-Open No. Hei 3-1
As disclosed in Japanese Patent No. 5864, if the charging device and the blade cleaner or the fab brush cleaner are simply integrated, even if the positioning accuracy with respect to the surface of the photoreceptor is improved, it is typified by ozone. The combination of a charger using a discharge electrode such as a charge wire, which easily generates active gas N _OX , and a blade shield having a high shielding property, heat generated by ozone or an optical eraser is transferred between the charger and the blade cleaner, and between the blade and the blade. Since it is easy for the cleaner or the like to be trapped, the surface of the cleaner blade and the surface of the photoreceptor are liable to be deteriorated rather than using the above-mentioned integrated structure. A charge eliminating sheet that does not generate heat and is used in place of an optical eraser has the same tendency as a cleaner blade in a combination that integrates with another. In particular, the cleaner blade is more susceptible to heat as it becomes smaller due to the miniaturization of the cleaning device.

Further, as disclosed in Japanese Patent Application Laid-Open No. 61-213870, merely ventilating the inside of the shield member of the charger and the surface of the photosensitive member facing the charger is required to provide the ventilation. The above problem does not reach the cleaner blade separate from the charger, and it is difficult to work efficiently on the cleaner blade part integrally supported with the charger, so that the above problem cannot be solved.

A main object of the present invention is to provide a cleaning device which is less likely to trap ozone and heat in a blade cleaner and which can eliminate the deterioration of the surface of the cleaner blade and the photoreceptor due to the ozone and heat. If necessary, the charging characteristics and the static elimination characteristics can be improved by integrating the blade cleaner with the charger or the static elimination sheet.

[0009]

According to a first aspect of the present invention, there is provided a cleaning device for cleaning a surface of an image carrier, a blade holder for holding the cleaner blade, and A charger provided in the vicinity of a cleaner blade for applying a charge to the image carrier; an opening provided in the blade holder; and an upstream side wall of the charger in a rotation direction of the image carrier. And an opening.

In such a configuration, the ozone air generated by the charger flows out through an opening provided on the upstream side wall of the charger in the rotation direction of the image carrier, and flows upstream of the charger in the rotation direction of the image carrier. After flowing toward the side of the cleaner blade located in the vicinity of the side of the image bearing member with the light irradiating portion for erasing residual charges on the surface of the image carrier, flowing out through the opening provided in the blade holder, The air is drawn into the charger and the blade holder from the surroundings, including the sides between them, so the ozone generated by the charger and the heat generated by the optical eraser and reaching the blade holder and the charger The air is taken out and discharged while being ventilated by the ozone air and the suctioned outside air without being kept in the charger and the blade cleaner, and the flow of the ozone air and the suctioned outside air is reduced by the charger and the blade. Since contact with the holder or the like to cool this directly, it is possible to prevent such deteriorated by heat ranging from light eraser to the cleaner blade and the surface of the photosensitive member ozone and charger and a blade holder or the like.

When the blade holder and the charger are integrally formed, the positional relationship between the two is uniquely determined, and their positioning with respect to the surface of the photoreceptor is performed in one-to-one correspondence by attaching one member. It is possible to achieve high accuracy, improve the charging performance and the cleaning performance, and furthermore, by integrating both of them, the charger and the blade cleaner and the ozone air and the suction outside air between them Since the flow is not hindered, the above-described function of preventing deterioration of the surface of the cleaner blade or the photosensitive member due to ozone or heat is not impaired.

Further, when the blade holder and the charger are supported by a support member which is detachably attached to a concentric portion of the image carrier, the blade holder and the charger, and hence the cleaner blade and the charging device. Since both of the containers are integrally positioned by the support member, a unique high-precision positioning state is achieved, and the support member is detachably attached to a concentric portion with the image carrier, so that the cleaner blade and the The charger can be attached and detached as a single unit with the support member, which is convenient for assembly, maintenance, inspection, repair, and replacement.The cleaner blade and the charger can be supported as long as the support member is mounted concentrically with the image carrier. The position is set at a predetermined distance from the rotation center of the image carrier while maintaining the high positioning accuracy on the member, and is positioned with high precision with respect to the surface of the image carrier pair. Since the, it is possible to ensure the high charging performance and cleaning performance.

A static elimination sheet for eliminating the residual charge of the image carrier, a static elimination sheet holder for holding the static elimination sheet, and a plurality of openings provided in the static elimination sheet holder; and the blade holder and the static elimination If the sheet holder and the sheet holder are integrally formed, the use of a static elimination sheet eliminates the problem of heat generation such as an optical eraser.In addition, the static elimination sheet holder is integrated with the blade holder of the blade cleaner, and is uniquely positioned with the cleaner blade, As in the case of the cleaner blade, positioning is performed with high accuracy by attaching one member to the image carrier in a one-to-one correspondence, so that the static elimination performance by the static elimination sheet is improved as well as the charging performance and the cleaning performance. In addition, the static elimination sheet has high shielding properties together with the cleaner blade, but the ozone air flowing out of the charger causes the static elimination sheet portion to pass through the blade holder and the static elimination sheet through the opening provided in the static elimination sheet holder like the cleaner blade. Air flows from the surroundings including the sides between the holders with suction, flows to the opening of the blade holder, and ozone generated by the charger is trapped in the charger, the static elimination sheet section, and the cleaning device. Instead, it is taken out and discharged while being ventilated by ozone wind and suction outside air generated by the charger, so that it is possible to prevent the cleaner blade, the surface of the photoconductor, and the charge removing sheet from being deteriorated by ozone.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

(Embodiment 1) In Embodiment 1, for example, a cleaning unit around a photosensitive drum, an optical erase unit, and the like as an image carrier commonly provided in various image forming apparatuses of an electrophotographic system, and Prevents the effects of ozone generated by the charger with discharge electrodes and heat generated by the optical eraser in the charging section, and also enhances the positioning accuracy of the cleaning device and the charging section with respect to the surface of the photosensitive drum. The cleaning performance and the charging performance are improved.

As shown in FIG. 1, a photosensitive drum 1 serving as an image carrier has a surface uniformly charged by a charger 2 projected onto a document image by a scanning optical system or modulated by an image signal. Upon receiving the laser beam, an electrostatic latent image is formed. This electrostatic latent image is developed with toner by a developing device (not shown) to be visualized. The visualized toner image is transferred onto a conveyed sheet, and the transferred sheet is subjected to a fixing process to form an image.

The residual toner on the surface of the photoreceptor drum 1 after transfer is cleaned by a cleaning device 3, and after the residual charge is removed by an optical eraser 4, it is charged again by a charger 2 to form a next electrostatic latent image. Prepare for the formation of For these reasons, the cleaning device 3, the optical eraser 4, and the charger 2 are arranged on the photosensitive drum 1 in FIG.
Are arranged in order in the rotation direction indicated by.

The present invention can be applied to an image forming apparatus using a belt-shaped photosensitive member as an image carrier or using a dielectric instead of the photosensitive member. The charger 2 charges the surface of the photosensitive drum 1 to a predetermined potential by discharging from the charge wire 2a, and generates an active gas N _OX represented by ozone and the like. A metal stabilizer plate 2b, which is a shield member surrounding the charge wire 2a from the back,
The grid mesh 2c is integrally provided in the opening facing the surface of the photoconductor drum 1b. The active gas N _OX is generated by any charger that employs various discharge electrodes such as a needle electrode, and is therefore an object of the present invention. Grid mesh 2c
Preferably has a predetermined gap between itself and the surface of the photosensitive drum 1, for example, a gap of 0.8 mm.
The charger 2 having the grid mesh 2c requires higher positioning accuracy with respect to the surface of the photosensitive drum 1.
However, the present invention can adopt a device that does not have such a grid mesh 2c.

The cleaning device 3 includes a cleaner blade 3
a is supported by a metal blade holder 3b so that the cleaner blade 3a comes into sliding contact with the surface of the photosensitive drum 1 at its tip. The shape and dimensions of the blade holder 3b are set with high precision so that the blade edge at the tip of the cleaner blade 3a does not impair the high-precision linearity set for uniform contact with the surface of the photosensitive drum 1. The one manufactured is adopted. Further, in order to easily ensure the positioning of the charger 2 and the cleaner blade 3a with respect to the surface of the photoreceptor drum 1, the blade holder 3b is connected to the back of the stabilizer 2b and is formed integrally with the charger 2.

Further, in order to prevent the photosensitive drum 1 and the cleaner blade 3a from being deteriorated by an active gas such as ozone generated by the charger 2 or heat generated by the optical eraser 4, the photosensitive drum of the charger 2 Upstream side of the rotation direction of the drum 1,
That is, in the first embodiment, the photosensitive drum 1 of the stabilizer 2b
An opening 2d is formed in the side wall 2b1 on the upstream side in the rotation direction of the blade holder 3b, and openings 3c and 3d are formed in the blade holder 3b. Specifically, the blade holder 3b has an opening 3c formed in a vertical wall to which the cleaner blade 3a is attached, and extends from the upper end of the vertical wall to the charger 2 side so as to have a stable plate 2b.
Openings 3d are respectively formed in the horizontal walls which are connected to the ceiling wall by spot welding, tacking screws, bonding or the like. The opening 3c is preferably formed as a continuous slit so as not to block the erase light emitted from the optical eraser 4 onto the surface of the photosensitive drum 1, and the other openings 2d,
Although 3d is not required to be continuous, it is preferably a slit in order to eliminate the influence of disturbance light during image exposure on the photosensitive drum 1.

Preferably, a plurality of slits are arranged discontinuously. Various types of cleaning blades 3a, such as those made of a single substance such as polyurethane rubber, fluorine rubber, or silicon rubber, or those bonded with another suitable material can be used.

As described above, the openings 3c and 3d provided on the blade holder 3b and the openings 2d provided on the upstream side wall 2b1 of the charger 2 in the rotation direction of the photosensitive drum 1 are provided.
, As indicated by the double arrow B in FIG.
The ozone wind generated in the charger 2 flows out through an opening 2d provided on the upstream side of the photosensitive drum 1 of the charger 2 in the rotation direction, and flows on the upstream side of the charger 2 in the rotation direction of the photosensitive drum 1. After flowing toward the cleaning device 3 located in the vicinity of the erasing light irradiation path from the optical eraser 4 via the irradiation path, it flows out through the opening 3d provided in the blade holder 3b.

Into the outflow of ozone, outside air is sucked in the charger 2 and the cleaning device 3 as indicated by a double arrow B1 from the periphery including the side between the cleaning device 3 and the charger 2. Therefore, the ozone generated by the charger 2 and the heat generated by the optical eraser 4 are taken out and discharged outside while being ventilated by the ozone wind and the suction outside air without being confined in the charger 2 and the cleaning device 3. Since the ozone wind and the flow of the ventilation flow from the surroundings come in contact with the stabilizer 2b, the blade holder 3b, the cleaner blade 3a and the like to directly cool the same, the surface of the cleaner blade 3a and the photosensitive drum 1 becomes ozone. Or deterioration due to heat can be prevented. When the openings 2d, 3d, and the like are provided discontinuously, if the mutual positions are shifted in the left-right direction so as to face each other, the flow of the ozone wind and the suctioned outside air becomes
Since the contact ratio with the stabilizer 2b, the blade holder 3b, and the like is improved, the cooling action is promoted, which is preferable.

Further, since the blade holder 3b and the charger 2 are integrally formed, the positional relationship between them is uniquely determined, and their positioning with respect to the surface of the photosensitive drum 1 is performed by attaching one member. Only one-to-one correspondence is achieved with high accuracy, and charging performance and cleaning performance can be improved. Particularly, in order to position the charger 2 with high precision with respect to the surface of the photoreceptor drum 1, mounting portions for positioning with high precision between the main body of the image forming apparatus and the detachable portion are provided at both ends of the charger 2. The positioning of the cleaner blade 3a with respect to the surface of the photosensitive drum 1 under the positional accuracy of the charger 2 is achieved only by integrating the blade holder 3b with the stabilizer plate 2b with high accuracy. can do. Of course, attachment portions to the main body of the image forming apparatus may be provided at both ends of the blade holder 3b in order to stabilize the positioning at high precision. Moreover, such a blade holder 3b and a stabilizer 2b
The integration of both does not hinder the flow of the ozone air between the charger 2 and the cleaning device 3 and between them, so that the function of preventing the surface of the cleaner blade 3a and the photosensitive drum 1 from deteriorating due to ozone or heat. Is not compromised.

Further, in the first embodiment, as shown in FIG. 1, an opening 2e is also provided at a portion where the back of the stabilizer 2b and the blade holder 3b are integrally connected to each other so as to prevent the ozone from flowing out. Of the photosensitive drum 1 and the cleaning blade 3a, the ventilation and cooling of the inside of the charger 2 and the surface of the photosensitive drum 1 facing the same can be promoted. The function of preventing deterioration due to ozone or heat can be further enhanced. In addition, an airflow guide flange 3b1 is formed at, for example, a lower edge of the opening 3d to guide ozone and suction outside air flowing out from the opening 3d, and through a more suitable position in the image forming apparatus. It is preferable because it can be diverged outside the apparatus.

In this case, if a fan is provided for sucking or blowing ozone or outside air flowing from the opening 3d in a predetermined direction or position, the cooling and ventilation functions can be further promoted, and the exhaust can also be improved. It can be suitably achieved.

(Embodiment 2) In Embodiment 2, as shown in FIG.
This shows a case in which the metal plate member and the stabilizer 2b of the charger 2 are integrally formed by a single metal plate member, thereby simplifying the structure, reducing the size, and reducing the number of parts and the number of assembly steps.

(Embodiment 3) In Embodiment 3, as shown in FIG. 3, instead of the optical eraser 4 of Embodiments 1 and 2, a charge removing sheet 6 for removing charges remaining on the photosensitive drum 1 is used.
And a static elimination sheet holder 7 for holding the static elimination sheet 6
And the opening 2 provided in the static elimination sheet holder 7.
d, 2e, 3d, etc., provided with an opening 7a provided under the same conditions and considerations.
Blade holder 3b and the static elimination sheet holder 7
Are integrated with each other, or they are integrally formed by a single metal plate.

As described above, when the static elimination sheet 6 is employed,
In addition to the advantage that there is no heat generation unlike the optical eraser, the static elimination sheet holder 7 is used as the blade holder 3
b, and is uniquely positioned with the cleaner blade 3a, and is positioned with high accuracy by attaching one member to the photosensitive drum 1 in a one-to-one correspondence like the cleaner blade 3a. In addition to the charging performance and the cleaning performance, the static elimination performance of the static elimination sheet 6 is also improved. Moreover, although the static elimination sheet 6 has a high shielding property together with the cleaning device 3, the openings 3d and 7a provided with the cleaning device 3 allow the ozone air flowing out of the charger 2 to clean the static elimination sheet 6 portion. The ozone generated by the charger 2 passes through the opening 3d of the blade holder 3b with the suction of the outside air from the periphery including the side between the blade 3a and the charge removing sheet 6, and the ozone generated by the charger 2 is discharged by the charger 2, Since the sheet 6 and the cleaning device 3 are taken out and discharged while being ventilated by ozone wind and suction outside air without being confined in the cleaning device 3, the cleaner blade 3a, the surface of the photosensitive drum 1, and the charge removing sheet 6 are deteriorated by ozone. Such a situation can be prevented. However, when the cleaner blade 3a and the static elimination sheet 6 are affected by heat from the fixing device, the flow of the ozone wind and the sucked outside air exerts a cooling action. This is the same in the first and second embodiments.

In the third embodiment, the cleaner blade 3a and the static elimination sheet 6 are integrally formed with each other by connecting the blade holder 3b to the charger in phantom lines as in the first embodiment. By integrating it with the charger 2, the positioning of these three members can be performed uniquely, and the positioning between the three members and the surface of the photosensitive drum 1 can be achieved with a single mounting with high accuracy.

The opening 3d of the blade holder 3b has an airflow guide flange 3b at its lower and upper edges.
Since 1, 3b2 are provided, it is easier to direct the outflowing ozone wind and the suctioned outside air in a predetermined direction than in the case of the first embodiment, and it is more preferable to perform suction or exhaust by a fan.

(Embodiment 4) In Embodiment 4, as shown in FIG. 4, a cleaning device 3 having a blade holder 3b and a charger 2 having a stabilizer 2b are used as photosensitive members as image carriers. It is supported by a metal support member 11 which is detachably attached to the concentric part of the body drum 1. The concentric portion may be a rotating shaft 1a at the center of rotation of both ends of the photosensitive drum 1, but in the first embodiment, each rotating shaft 1a
Are used as concentric parts, and oval-shaped holes 11a of a pair of left and right support members 11 located at both ends of the photosensitive drum 1 are respectively fitted to the left and right rotating shafts 1a. A pair of left and right support members 1 are mounted so that they can be fitted and detached from the oval-shaped external part by being fitted from the axial direction and detachable by screws or retaining collars.
The blade holder 3b is integrally formed and provided between the front end portions of the charger 1 and the stabilizer 2b of the charger 2 is integrally supported by welding or screwing. The blade holder 3b may be formed separately from the support member 11 and may be integrally connected to the support member by welding, screw fastening, or the like. Other configurations are described in Embodiment 1,
The same members and portions are denoted by the same reference numerals, and overlapping illustration and description are omitted.

As a result, the blade holder 3b and the charger 2, that is, both the cleaner blade 3a and the charger 2 are integrally supported by the support member 11 to achieve a unique high-precision positioning state. Are attached to the bearing member 12 which is concentric with the photosensitive drum 1 so that the cleaner blade 3a and the charger 2 can be attached and detached together with the support member 11 as a unit. It is convenient for replacement, and as long as one of the support members 11 is mounted on the bearing member 12 which is concentric with the photosensitive drum 1, the cleaner blade 3a and the charger 2 can maintain the high positioning accuracy on the support member 11. Is maintained at a predetermined distance from the rotation center of the photosensitive drum 1 and is positioned with high precision with respect to the surface of the photosensitive drum 1. Since, it is possible to secure a high charging performance and cleaning performance.

(Embodiment 5) In Embodiment 5, as shown in FIG. 5, instead of the oval hole 11a in Embodiment 4 of the support member 11, a slit portion having this hole 11a opened downward is provided. 11b, so that attachment and detachment to the bearing member 12 in the fourth embodiment can be easily performed from a direction perpendicular to the axis. The other configuration and operation and effect are the same as those of the fourth embodiment, and therefore, duplicated illustration and description are omitted.

[0035]

According to the first aspect of the present invention, the ozone generated by the charging device and the heat generated by the optical eraser are changed by the ozone wind generated by the charging device and the external air which accompanies the ozone wind generated by the charging device. The ozone generated in the air and the heat generated by the optical eraser and reaching the blade holder and the charger are taken out and discharged while being ventilated without being confined in the charger and the blade cleaner. Contacts the charger and the blade holder and cools it directly, preventing the surface of the cleaner blade and the photoreceptor from deteriorating due to ozone and heat from the optical eraser to the charger and the blade holder. The durability life of the cleaning blade and the image carrier can be improved.

According to the second aspect of the present invention, the cleaning performance and the charging performance are improved by integrating the blade holder and the charger to secure the mounting accuracy of the cleaner blade and the charger by attaching one member. Can be.

According to the third aspect of the present invention, the cleaner blade and the charger are attached together with the support member by integrating the blade holder and the charger and detachably attaching one support member to the image carrier and the concentric portion. It can be attached and detached as a single unit, convenient for assembly, maintenance, inspection, repair, and replacement. The cleaner blade and the charger can be positioned at a high position on the support member as long as the support member is mounted concentrically with the image carrier. Since the position is set at a predetermined distance from the center of rotation of the image carrier while maintaining accuracy, and it is positioned with high precision with respect to the surface of the image carrier, high charging performance and cleaning performance can be secured.

According to the fourth aspect of the present invention, the use of the static elimination sheet eliminates the problem of heat generation as in the optical eraser.
By integrating the static elimination sheet holder and the blade holder, both are uniquely positioned, and are positioned with high accuracy by attaching one member to the image carrier in a one-to-one correspondence like the cleaner blade. Therefore, along with the charging performance and the cleaning performance, the static elimination performance by the static elimination sheet is also improved, and the static elimination sheet has a high shielding property together with the cleaner blade, but like the cleaner blade, the opening provided in the static elimination sheet holder, The ozone generated by the charger is taken out and discharged while being ventilated by the ozone wind generated by the charger and the outside air without being trapped in the charger, the static elimination sheet, and the cleaning device. The surface of the sheet and the static elimination sheet can be prevented from being deteriorated by ozone. , It is possible to improve the cleaning blade, and the image bearing member of the service life.

[Brief description of the drawings]

FIG. 1 is a sectional view showing Embodiment 1 of the present invention.

FIG. 2 is a sectional view showing Embodiment 2 of the present invention.

FIG. 3 is a sectional view showing a third embodiment of the present invention.

FIG. 4 is a side view showing a fourth embodiment of the present invention.

FIG. 5 is a partial side view showing a fifth embodiment of the present invention.

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 Photoreceptor drum 2 Charger 2a Charge wire 2b Stabilizer 2d, 2e, 3c, 3d, 7a Opening 3 Cleaning device 3a Cleaner blade 3b Blade holder 6 Static elimination sheet 7 Static elimination sheet holder 11 Support member 11a Hole 11b Slit part 12 Bearing Element

Claims (4)

[Claims] 1. A cleaner blade for cleaning a surface of an image carrier, a blade holder for holding the cleaner blade, a charger provided near the cleaner blade for applying a charge to the image carrier, and the blade. A cleaning device comprising: an opening provided in a holder; and an opening provided in an upstream side wall of the charger in a rotation direction of the image carrier. 2. The cleaning device according to claim 1, wherein the blade holder and the charger are integrally formed. 3. The cleaning according to claim 1, wherein the blade holder and the charger are supported by a support member that is detachably attached to a concentric portion of the image carrier. apparatus. 4. A charge removing sheet for removing charge remaining on the image carrier, a charge removing sheet holder for holding the charge removing sheet, and an opening provided in the charge removing sheet holder. The cleaning apparatus according to any one of claims 1 to 3, wherein the cleaning sheet holder and the charge removing sheet holder are integrally formed.