JPH06318018A - Cleaning device and production of cleaning brush used therein - Google Patents

Abstract

PURPOSE:To smoothly and surely remove a toner filming layer by providing a brush part capable of removing the toner filming layer at one part of a cleaning brush. CONSTITUTION:The brush part capable of removing the toner filming layer produced at the part (area L) of the surface area of a photosensitive body 1 being an image carrier on which a separation pawl 10 abuts is provided at one part of the cleaning brush 23. As for the brush part, one part of the brush 23 is made a loop state brush 23A and the other part is made a straight-brisle brush 23B. Since the brush 23A is stiffer than the brush 23B, its rubbing force on the photosensitive body 1 gets stronger. Therefore, the thin toner filming layer produced in the area L caused by the abutting of the separation pawl 10 is smoothly and surely removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device for an image forming apparatus and a method for manufacturing a cleaning brush used in this cleaning device.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine, a printer or a facsimile, an electrostatic latent image is formed on an image carrier,
It is known that the electrostatic latent image is visualized as a toner image and the toner image is transferred to a recording medium.

FIG. 7 shows a schematic structure of an example of such an image forming apparatus. In describing an image forming process by the image forming apparatus, the conventional problems will be clarified below. And

In FIG. 1, reference numeral 1 denotes a drum-shaped photosensitive member which is an example of the constitution of the image bearing member, and the photosensitive member 1 is rotationally driven in the direction of the arrow shown in the figure. During this rotation, the surface of the photoconductor 1 is uniformly charged by the charging charger 2. Then, the exposure unit 3 performs image exposure or optical writing on the charged surface to form a predetermined electrostatic latent image on the surface of the photoconductor.

Thereafter, the electrostatic latent image is visualized as a toner image by the developing device 4. On the other hand, a transfer paper 5 which is an example of a recording medium is sent from a paper feed unit (not shown) toward the transfer belt 7 through the registration roller pair 6, and the sent transfer paper 5 is the transfer belt 5. 7
The transfer area 8 is carried while being pressed on the photoconductor 1.
Pass through. During this passage, the toner image formed on the surface of the photoconductor 1 is transferred to the transfer paper 5.

Generally, in this type of image forming apparatus, the transfer paper 5 is separated from the photoconductor 1 after the toner image is transferred onto the transfer paper. That is, the transfer paper is separated from the surface of the photoconductor in order to surely face the transfer paper to the fixing device 9 for fixing the transfer toner image.

As a method of separating the transfer paper from the photosensitive member, a transfer belt method in which the transfer paper is electrostatically adsorbed to the transfer belt and then separated and conveyed, or a transfer paper is provided on the back surface of the transfer paper by a corona transfer device. The electrostatic charge is neutralized by a corona discharge having a polarity opposite to that of the corona transfer device, the electrostatic attraction between the transfer paper and the photoconductor is reduced, and the corona is separated by the weight and waist of the transfer paper. Separation methods and the like are currently the mainstream.

However, when a transfer paper having a weak stiffness or a thin transfer paper is used, the transfer paper is not separated if the environmental performance is changed or the separation performance is deteriorated due to dirt on the transfer paper separator. Sometimes.

When a transfer sheet that has not been separated by the transfer sheet separating apparatus adopting the transfer belt method or the corona separating method enters the cleaning apparatus described later, an accident such as a paper jam in the cleaning apparatus occurs.
In the worst case, the photoconductor may be damaged.

In order to avoid such a situation, in this type of image forming apparatus, a separation claw is provided as an auxiliary separation device other than the transfer paper separation device. In FIG. 7, reference numeral 10 indicates an example of the separation claw, which is in contact with the surface of the photoconductor 1.

After the transfer, when the transfer paper that has passed through the transfer area 8 is not separated from the surface of the photoconductor 1 and remains attached to the photoconductor 1, the transfer paper is separated by the separation claw 10. And is sent toward the fixing device 9. Thus, the separation claw 10 separates the transfer paper 5 on which the toner image is transferred from the photoconductor 1.

In FIG. 7, reference numeral 12 is a cleaning device which is opposed to the photoconductor 1. The cleaning device 12 rubs against the photoconductor 1 to transfer the toner image to the photoconductor. A cleaning brush 13 for cleaning the surface is provided.

After the transfer of the toner image, the toner which has not contributed to the transfer remains on the surface of the photosensitive member, and the adhered toner is scraped off by the cleaning brush 13. Then, the toner not removed by the brush is removed by the cleaning blade 14 located on the downstream side. The toner thus removed is once stored in the cleaning casing 15 of the cleaning device and then discharged to the outside of the casing. The cleaning brush 13 is the photosensitive member 1.
It is rotatively driven in the direction of the arrow shown in the figure with a relative speed difference so as to rub against.

The photoconductor 1 whose surface has been cleaned is initialized by the charge removal function of the charge removal lamp.

The separation claw 10 as a separation assisting means is installed between the transfer belt 7 and the cleaning device 12, and is mounted on the stay shaft 16 arranged in parallel with the photoconductor 1.
For example, they are attached to each other at two positions with a space therebetween. The separation claw 10 has a width of the claw portion 10a (a thickness width in the axial direction of the photoconductor 1) of, for example, about 0.5 mm. If the separation claw easily damages the photoconductor, the damage is caused. In order to reduce the above, the separation claw is reciprocally driven in the axial direction of the photoconductor 1 by a stroke amount of, for example, about 10 mm.

After that, in the case where the separation claw 10 does not reciprocate in the axial direction of the photoconductor 1, the photoconductor portion corresponding to the thickness width thereof will be referred to as a part to which the separation claw abuts.
Further, in the case of the reciprocating structure, the photosensitive member portion in the reciprocating region of the separating claw is referred to as a portion with which the separating claw abuts.

Since the separation claw 10 is installed between the transfer belt 7 and the cleaning device 12, the transfer residual toner 17 inevitably enters the separation claw portion as shown in FIG. The transfer residual toner is blocked by the separation claw 10 that is in contact with the photoconductor 1, and when the blocking amount increases, the toner drops from the claw portion onto the transfer paper and stains the image. .

Therefore, it is also known to use a separating claw 10 'as shown in FIG. The separation claw 10 ′ is chamfered at the tip claw portion in contact with the photoconductor so that a wedge-shaped space 18 is formed between the separation claw 10 ′ and the photoconductor 1. That is, the portion into which the transfer residual toner 17 enters is formed into a wedge shape so that it can pass under the separation claw 10 '.

Recently, a toner having a lower melting point tends to be used. For example, the outflow starting temperature is 106
When a toner having a relatively low melting point of 70 ° C. and a softening temperature of 76 ° C. is used, a toner filming layer may be formed on the photosensitive member portion where the separation claw abuts when the photosensitive member temperature is about 40 ° C. or higher. become. In particular, in the case of the separation claw 10 'shown in FIG. 9, when the transfer residual toner 17 slips under the separation claw 10', the transfer residual toner is pressed against the photoconductor 1 by the separation claw 10 ', and the toner fill is performed. The ming layer is generated. Separation claw 10 of the type shown in FIG.
Also forms a toner filming layer on the photoconductor 1.

Since such a toner filming layer is formed by a very weak pressure and is very thin, it is difficult to remove it even with the cleaning blade 14 pressed against the surface of the photoconductor 1, and this removal is left as it is. Then, it also causes deterioration of image quality.

[0021]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cleaning device capable of smoothly and surely removing a toner filming layer caused by abutment of a separating claw.
Another object of the present invention is to provide a method of manufacturing a cleaning brush used in the cleaning device.

[0022]

In order to achieve the above object, the present invention provides an image carrier on which a toner image is formed,
An image forming apparatus comprising at least a separation claw that comes into contact with the image carrier and a cleaning device that is opposed to the image carrier, wherein the separation claw is used for carrying a recording medium having a toner image transferred thereon. The image is a separation claw that separates from the body, and the cleaning device is a cleaning device that includes a cleaning brush that slides on the image carrier to clean the surface of the image carrier after transfer. In the forming apparatus, there is provided a cleaning device in which a part of the cleaning brush is provided with a brush portion capable of removing a toner filming layer generated in a portion of the surface area of the image carrier on which the separation claw comes into contact. It is a proposal.

In order to achieve the above-mentioned object, the present invention also comprises an image carrier on which a toner image is formed, a separation claw which abuts on the image carrier, and a cleaning device which is opposed to the image carrier. An image forming apparatus including at least the separating claw, wherein the separating claw is a separating claw for separating the recording medium on which the toner image is transferred from the image carrier, and
The image forming apparatus is a cleaning apparatus including a cleaning blade that contacts the image carrier to clean the surface of the image carrier after transfer. The present invention proposes a cleaning device provided with means for forming a protective film having lubricity on the contacting portion.

It is effective to use a part of the cleaning brush as a loop brush and another part as a straight bristle brush.

It is effective that the cleaning brush is a straight bristle brush, and a brush portion having a longer bristle length than other portions is used so that the toner filming layer can be removed. Is.

Further, it is effective to first make the entire cleaning brush into a loop-shaped brush and finish the other brush portion by shirring to form a straight-hair brush.

Furthermore, the entire cleaning brush is made into a straight bristle brush having a uniform bristle length, the other brush portion is finished by shirring, and the bristle length of a part of the brush portion is
It is effective to make it relatively longer than the other brush parts.

[0028]

Embodiments of the present invention will now be described in detail with reference to the drawings. The overall configuration and operation of the image forming apparatus including the cleaning device described below are the same as those shown in FIGS. 7 to 9, and therefore description thereof will be omitted.

FIG. 1 is a diagram showing a relative positional relationship among a cleaning brush, a photoconductor, and a separation claw provided in a cleaning device according to an embodiment of the present invention.

In the figure, a pair of separation claws 10, 10
Are fixed so as not to rotate with respect to the stay shaft 16 at intervals. The stay shaft 16 is supported movably in the axial direction by guide means (not shown), and is pressed against the cam surface 21A of the cam member 21 by the force of the compression spring 19. When the cam member 21 rotates, the stay shaft 1
6 is reciprocated in this axial direction. That is, in order to reduce the damage to the photoconductor 1, the separation claw 10 that contacts the photoconductor 1 reciprocates by the distance L.

A reference numeral 23 in FIG. 1 is a cleaning brush of a cleaning device (see FIG. 7) for cleaning the surface of the photosensitive member 1. The cleaning brush 23 is a feature of the embodiment of the present invention. A brush portion that enables removal of the toner filming layer that is generated in a portion (L region) of the surface area of the photoconductor 1 that is an example of an image bearing member and is in contact with the separation claw 10 is partially provided in It is in the point provided.

The example of the cleaning brush 23 shown in FIG. 1 uses a loop-shaped brush 23A for such a brush portion. That is, a part of the cleaning brush 23 is a loop-shaped brush 23A and the other part is a straight-hair brush 23B.

The loop brush 23A is a straight bristle brush 2
Since the stiffness is stronger than that of 3B, the rubbing force on the photoconductor 1 is large, and as a result, the thin toner filming generated in the L area due to the contact of the separation claw 10 as described above. The layer can be removed smoothly and reliably.
Regarding the technique of using a loop-shaped bristle body for a cleaning brush, for example, the technique disclosed in Japanese Utility Model Laid-Open No. 63-122371 has already been proposed.

The cleaning brush 23 shown in FIG.
For example, on the outer peripheral surface of the brush core metal 24, the loop-shaped brush 2
Base cloth (not shown) in which 3A and straight hair brush 23B are woven
It is made by winding. As the material of the brush, for example, a conductive fiber such as SA-7 manufactured by Toray Industries, Inc. may be selected, or an insulating fiber such as polyester may be selected. Conventionally, the loop-shaped brush 23A is compulsorily scraped off the photoconductor 1, so that the effect may be damaged but the photoconductor 1 may be damaged.
Since only the portion corresponding to the contact position of 0 is loop-shaped, the damage can be minimized.

The cleaning brush 33 shown in FIG.
The whole is a straight bristling brush, and a part (L region) of the brush is more brushed than other brush parts so that the toner filming layer formed on the photoconductor part which the separation claw abuts can be removed. It is also used as a brush part with long legs. That is, the brush portion 33A corresponding to the contact area L of the separation claw is
For example, 0.5 to 2.0 than the other brush portion 33B.
I made it longer by about mm.

Also in this way, the amount of brush biting in the separation claw contact area can be increased. The rubbing force of the brush with respect to the photoconductor can be increased so that the toner filming layer can be removed. Also in this case, the damage to the photoconductor is small, and it is possible to suppress the torque increase when the cleaning brush, the photoconductor, and the like are rotationally driven.

Here, when the cleaning brush 23 shown in FIG. 1 is produced, if the entire cleaning brush is first made into a loop-shaped brush and the other portion is finished by shirring to form a straight-hair brush, the cleaning brush is
It becomes possible to manufacture easily and accurately.

A reference numeral 25 in FIG. 3 is a shirring roller, and the roller 25 has a blade portion only in the B portion other than the A portion. First, wrap and fix the loop-shaped brush base fabric on the brush core metal 24,
Then, the tip of the loop brush is applied to the shirring roller 25, and the roller 25 is rotated as shown in FIG. In the figure, for the sake of convenience, what is indicated by reference numeral 23 is a material of the cleaning brush, and as shown in the figure, while rotating the cleaning brush material 23, the shearing roller 25 is rotated with a relative speed difference,
Cut the tip of the loop brush with the blade.

Then, the brush portion corresponding to the A portion is left, and the other brush portions corresponding to the B portion become a straight bristle brush. That is, the brush portion corresponding to the L region (FIG. 1) is a loop-shaped brush, and the other portions are straight-brushed brushes.

Further, the entire cleaning brush is a straight bristle brush having a uniform bristle length, the other brush portion is finished by shirring, and a part (L region) of the brush portion is more than the other brush portion. The hair length may be relatively long. That is, of all the straight bristling brushes, L
By cutting the tip side of the brush portion excluding the region (FIG. 2) with the blade portion (FIG. 3) of the shearing roller 25, a cleaning brush as shown in FIG. 2 can be manufactured.

By any of the manufacturing methods, the cleaning brush can be manufactured easily and accurately.

FIG. 5 is a schematic configuration diagram of a cleaning device of an embodiment corresponding to another invention.

The cleaning device 22 has a cleaning brush 13, a cleaning blade 14, a toner conveying screw member 26, etc., and the cleaning brush 13 among them is arranged so as to rub against the photoreceptor 1. It is rotationally driven with a speed difference. The cleaning blade 14 contacts the photoconductor 1 with a predetermined pressure to clean the surface of the photoconductor after the transfer of the toner image. Both members 13, 1
The toner removed by 4 is collected in the casing 27, and by the rotation of the toner carrying screw member 26,
It is discharged to the outside of the casing 27.

The cleaning device is provided with a means for forming a protective film having lubricity on a portion of the surface area of the photoconductor 1 where the separation claw comes into contact (area L in FIG. 1).

As shown in FIG. 5, a solid lubricant 28 made by hardening zinc stearate or the like is installed in the casing 27 so as to be in contact with the cleaning brush 13. As the solid lubricant 28, one having a width (width in the axial direction of the cleaning brush 13) of approximately L (FIG. 1) is used, and is located at a position corresponding to the contact portion of the separation claw. It is arranged.

A small amount of the lubricant from the solid lubricant 28 is applied onto the photosensitive member 1 via the cleaning brush 13.
That is, a protective film having lubricity is formed on the portion where the separation claws abut. Since the toner filming layer is formed on the protective film by the separating claw, the cleaning blade 14 can remove the toner filming layer for each lubricant protective film.

Lubricants such as zinc stearate are
For example, as disclosed in Japanese Patent Laid-Open No. 57-17973, it is useful for improving the cleaning property.
If it is accumulated in a developing device or the like, it may adversely affect the image.

However, in the present invention, since the lubricant is applied only to the abutting portion of the separating claw, the amount of the accumulated lubricant is extremely small, and the influence on the image can be minimized. As the type of lubricant, in addition to zinc stearate,
Barium stearate, lead stearate, iron stearate, nickel stearate, cobalt stearate, copper stearate, strontium stearate, calcium stearate, cadmium stearate, magnesium stearate, zinc oleate, manganese oleate, iron oleate. , Cobalt oleate, lead oleate, magnesium oleate, copper oleate, zinc palmitate, cobalt palmitate, copper palmitate, magnesium palmitate, aluminum palmitate,
Metal salts of fatty acids such as calcium palmitate, lead caprylate, lead caproate, zinc linolenate, cobalt linolenate, calcium linolenate, zinc licolinolenate and cadmium licolinolenate, for example relatively higher order stearic acid and palmitic acid. Fatty acids, such as Cab-O-, which is commercially available from Kapot Corporation
There are colloidal high salt silica powders such as Sil.

In the cleaning device 32 shown in FIG. 6, a lubricant applying roller 29 is provided between the cleaning brush 13 and the solid lubricant 28, and the lubricant from the solid lubricant 28 is applied to the lubricant. It is adapted to be applied onto the photoconductor 1 via the roller 29 and the cleaning brush 13. The roller 29 can also be used as a flicker member that knocks off the toner attached to the cleaning brush 13.

Since the lubricant is applied to the lubricant applying roller 29 and then to the cleaning brush 13 and the photosensitive member 1 in this order, a smaller amount of the lubricant can be applied. If the coating amount of the lubricant on the photoconductor 1 is increased, the developability is deteriorated. However, if the lubricant is coated in a small amount, such a problem is less likely to occur. or,
The lubricant thin film can be stably formed even in the long term. Other configurations and operations are the same as those of the embodiment shown in FIG.

The present invention is applicable to an image forming apparatus using a drum-shaped photoconductor or a belt-shaped photoconductor as an image carrier, and a cleaning device in an image forming apparatus using an image carrier other than such a photoconductor. Of course, it can be widely applied. Further, the cleaning device can be configured by appropriately combining the above-described configurations.

[0052]

According to the cleaning device of the first aspect of the present invention, the toner filming layer on the image carrier caused by the contact of the separation claw can be smoothly and surely removed, and the image quality can be improved. Can be prevented from lowering.
Further, since a dedicated member for removing the toner filming layer is not required, the cleaning device having a simple structure can be obtained.

According to the cleaning device of the second aspect, since only the portion that contacts the separation claw is the loop brush, it is possible to minimize damage to the image carrier.

According to the cleaning device of the third aspect, since only the part that abuts the separation claw is a straight bristling brush having a long bristle length, damage to the image carrier can be minimized. Further, it is possible to suppress torque increase when driving the cleaning brush, the image bearing member, or the like.

According to the manufacturing method of the fourth and fifth aspects, the cleaning brush can be manufactured easily and accurately.

According to the cleaning device of the sixth aspect, the toner filming layer on the image carrier caused by the contact of the separation claw is smoothed by the cleaning blade.
In addition, it can be reliably removed, and the image quality can be prevented from deteriorating. Further, since the lubricant is applied only to the separation claw contact portion, there is no possibility that the lubricant will be accumulated in a large amount in the developing device or the like, and the influence on the image can be minimized.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a relative positional relationship among a cleaning brush, a photoconductor, and a separation claw included in a cleaning device according to an exemplary embodiment of the present invention.

FIG. 2 is a diagram showing another example of a cleaning brush.

FIG. 3 is a manufacturing method diagram when a cleaning brush is manufactured by a shirring method.

FIG. 4 is a side view of the system diagram of the above.

FIG. 5 is a schematic configuration diagram of a cleaning device according to another embodiment.

FIG. 6 is a schematic configuration diagram of a cleaning device according to still another embodiment.

FIG. 7 is a schematic configuration diagram around a photoconductor of an image forming apparatus used for explaining a conventional technique.

FIG. 8 is a configuration diagram around a separation claw for explaining generation of a toner filming layer.

FIG. 9 is a configuration diagram around a separation claw for explaining that a toner filming layer is formed in a chamfered separation claw.

[Explanation of symbols]

 1 Drum-Shaped Photoreceptor as Image Carrier 10 Separation Claw 14 Cleaning Blade 22 Cleaning Device 23 Cleaning Brush 23A Loop Brush 23B Straight Hair Brush 28 Solid Lubricant 32 Cleaning Device 33 Cleaning Brush 33A Brush Part

Claims (6)

[Claims] 1. An image forming apparatus comprising at least an image carrier on which a toner image is formed, a separation claw abutting the image carrier, and a cleaning device facing the image carrier. The separation claw is a separation claw that separates the recording medium on which the toner image is transferred from the image carrier, and the cleaning device slides against the image carrier to form the image after transfer. In an image forming apparatus that is a cleaning device including a cleaning brush that cleans the surface of a carrier, a part of the cleaning brush is generated in a portion of the surface area of the image carrier where the separation claw abuts. A cleaning device provided with a brush portion capable of removing the toner filming layer. 2. The cleaning device according to claim 1, wherein a part of the cleaning brush is a loop-shaped brush and the other part is a straight bristle-shaped brush. 3. The cleaning brush is a straight bristle brush, and a brush portion having a longer bristle length than the other portion is formed so that the toner filming layer can be partially removed. The cleaning device according to. 4. A method of manufacturing a cleaning brush used in a cleaning device according to claim 2, wherein the entire cleaning brush is first formed into a loop-shaped brush, and the other brush portion is finished by shirring to form a straight-brushed brush. 5. The entire cleaning brush is a straight bristle brush having a uniform bristle length, the other brush portion is finished by shirring, and the bristle length of a part of the brush portion is larger than that of the other brush portion. The method of manufacturing a cleaning brush used in the cleaning device according to claim 3, wherein the cleaning brush is relatively long. 6. An image forming apparatus comprising at least an image carrier on which a toner image is formed, a separation claw abutting against the image carrier, and a cleaning device facing the image carrier. The separation claw is a separation claw that separates the recording medium on which the toner image is transferred from the image carrier, and the cleaning device contacts the image carrier and the surface of the image carrier after the transfer. In the image forming apparatus, which is a cleaning device having a cleaning blade for cleaning the surface of the image carrier, a means for forming a protective film having lubricity is provided on a portion of the surface area of the image carrier on which the separation claw abuts. A cleaning device characterized by the above.