JPH0895449A - Cleaning device for image forming device - Google Patents

Abstract

PURPOSE: To provide a cleaning device capable of using a cleaning blade having a small included angle and preventing a large amount of toner from riding on the rake face of the edge when a rake in a contact part at the time of bringing the edge of the cleaning blade into press-contact with an image carrier, is made small. CONSTITUTION: The cleaning device 13 is provided with the cleaning blade 16 consisting of an elastic body and the edge 17 of the cleaning blade 16 is brought into press-contact with the surface of a photoreceptor drum 1, to remove the toner stuck thereto. The included angle of the edge 17 is made small and the angle (rake) αformed by the surface in the rotational direction of the drum 1 and the surface of the edge 17 turned into the direction opposite to the rotational direction of the drum 1, in the contact part when the edge 17 comes into press-contact with the drum 1, is set <60 deg.. Moreover, the rake α is set larger than an angle (angle of repose) β formed by the foot of the heap of the toner when it is heaped on the horizontal plane.

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 electrophotographic image forming apparatus such as an electrostatic copying machine or a printer.

[0002]

2. Description of the Related Art In general, electrophotographic image formation is
A photosensitive drum, which is an image carrier, is charged and exposed to develop toner on the photosensitive drum, and the toner is transferred to a sheet. When the transfer process is completed, the photosensitive drum is cleaned and discharged, while the toner is fixed on the paper. During this series of steps,
In cleaning, a blade cleaning method in which a cleaning blade is brought into pressure contact with a rotating photosensitive drum to drop toner is widely used because the apparatus has a simple structure and can be manufactured at low cost. This type of cleaning blade is usually formed in a rectangular plate shape from an appropriate elastic body such as polyurethane and is configured to come into contact with the entire width of the image forming area of the photosensitive drum.

FIG. 8 shows a conventional typical usage of a cleaning device using a cleaning blade.
In the figure, reference numeral 1 indicates a photosensitive drum, which is rotated in the direction of the arrow. The surface of the photosensitive drum 1 is partially charged, and the toner 2 is attached to the charged portion by exposure. Photoconductor drum 1
After the toner 2 is transferred to a sheet (not shown) in accordance with the rotation of, the remaining toner 2 reaches the cleaning device 3. In the cleaning device 3, the rigid mounting member 4c is fixed to the supporting portion 4a which is a rigid body, and the mounting member 4c is fixed.
The cleaning blade 6 is fixed to. The residual toner 2 is blocked by the edge 7 of the cleaning blade 6 and scraped off from the surface of the photosensitive drum 1. Such a cleaning device is disclosed, for example, in JP-A-62-75576 or JP-A-4-172.
It is disclosed in Japanese Patent No. 486.

However, in the cleaning device 3 as described above, the angle Φ formed by the edge 7 of the cleaning blade 6 and the surface of the photoconductor 1 on the side where the photoconductor 1 rotates is an acute angle. Then, the toner is accumulated between the surface of the edge 7 and the surface of the photoconductor 1. When the toner is deposited in this way, the toner 2 may be present between the edge 7 and the surface of the photoconductor 1 depending on the pressure contact force applied to the cleaning blade 6 or the contact state between the edge 7 and the surface of the photoconductor 1. There is a case in which so-called filming occurs in which the film penetrates and is pressed here to form a film on the surface of the photoconductor 1. Further, the toner 2 is provided between the edge 7 and the surface of the photoconductor 1.
May pass without being crushed, and may be conveyed while being attached to the surface of the photoconductor 1, and reliable cleaning may not be possible. Such poor filming or cleaning causes deterioration of the formed image.

Further, in recent years, a capsule toner has been proposed in which a core material containing a binder, a colorant, a release agent, an external additive and the like is enclosed in an outer shell. In this capsule toner, the outer core is pressed and crushed to fix the inner core material to the paper by this pressure. Therefore, it is not necessary to heat at the time of fixing as in the conventional case, and it is excellent in labor saving. Generally, such a capsule toner is easily crushed even with a weak pressure, and if it is conveyed to the cleaning device 3 while remaining on the photoconductor 1, the cleaning blade 6 as described above causes
There is a problem that the outer shell is easily broken and the core material is fixed to the surface of the photosensitive drum 1.

In order to avoid such a phenomenon, for example, JP-A-62-58472 and JP-A-2-216178 propose a cleaning device having an angle Φ of 90 ° or more, as shown in FIG. Has been done. According to these devices, the toner 2 attached to the surface of the photoconductor 1 and conveyed, and reaching the contact portion between the edge 7 and the photoconductor 1, is not transferred to the edge 7.
It is scraped up by the rake face 7a (the face in the direction in which the photoconductor 1 rotates) and moves along the rake face 7a, so that it quickly separates from the contact portion, and the accumulation of the toner 2 is prevented. Among these publications, in Japanese Utility Model Laid-Open No. 62-58472, the angle θ forming the edge 7 of the cleaning blade 6 is
(Hereinafter referred to as "blade angle") is set to about 70 °, and the blade angle θ is set to 85 ° to 90 ° in JP-A-2-216178.

By the way, the cutting edge angle θ of the cleaning blade 6 which has been practically used up to now is at least 62 °
It is 70 ° as disclosed in Japanese Patent Laid-Open No. 58472. The reason for this is that if the cutting edge angle θ is small, the thin portion of the edge 7 becomes long, and the cleaning blade 6 may rise due to the reaction force when removing the toner 2, and the toner 2 may not be removed. . In addition, the cutting edge angle θ
Is small, the edge 7 is moved to the photosensitive drum 1 with sufficient pressure contact force.
This is also because the toner 2 passes between the edge 7 and the photoconductor drum 1 and filming still occurs, or reliable cleaning cannot be performed.

[0008]

However, theoretically, the edge 7 of the cleaning blade 6 having a small cutting edge angle θ is brought into contact with the photoconductor 1 and the rake face 7a of the edge 7 is formed.
Is as parallel as possible to the surface of the photoconductor 1, that is, the complementary angle of the angle Φ (hereinafter referred to as “rake angle”) α
The smaller the value, the more the toner 7 on the photoconductor 1 is picked up to the edge 7 by the edge 7, which is preferable. Further, for example, when using a capsule toner, if the rake angle α is less than 60 °, the toner can be cleaned without destroying the capsule. The problem here is that the cleaning blade 6 floats up as described above, or a sufficient pressure contact force is not given, but regarding these problems as well, a material having large rigidity is selected as the cleaning blade 6. Alternatively, it may be possible to solve the problem by devising a method of supporting the cleaning blade 6.

However, when the rake angle α becomes too small, a large amount of toner 2 rides on the rake face 7a of the edge 7, so that the toner 2 gradually accumulates at the contact portion between the edge 7 and the photosensitive drum 1. Finally, the rake face 7a of the edge 7 is covered by the preceding toner 2,
The subsequent toner 2 is not removed at all. Then, the total weight of the toner 2 accumulated on the contact portion between the edge 7 and the photoconductor 1 becomes large, and the toner 2 pressed against this increases.
Easily pass between the edge 7 and the photosensitive drum 1,
After all, filming and cleaning failure may occur.

The present invention has been made in order to solve the above-mentioned problems, and uses a cleaning blade having a small blade edge angle in a contact portion when the edge of the cleaning blade is pressed against the image carrier. An object of the present invention is to provide a cleaning device for an image forming apparatus that prevents a large amount of toner from riding on the rake face of the edge when the rake angle is reduced.

[0011]

In order to solve the above-mentioned problems, a cleaning device for an image forming apparatus according to the present invention removes toner adhering to the surface of a rotating image elastic member by pressing it. In a cleaning device of an image forming apparatus equipped with a cleaning blade provided with an edge, the surface of the contacting portion when the edge is pressed against the image carrier in the rotation direction side, and the image of the edge. The angle formed by the surface of the carrier facing the direction of rotation is less than 60 °, and is larger than the angle formed by the bottom of the mountain of the toner when the toner is deposited on the horizontal surface. .

[0012]

According to the cleaning device of the image forming apparatus having the above-described structure, the surface of the image carrier in the rotation direction side at the contact portion when the edge of the cleaning blade is pressed against the image carrier and the rotation of the image carrier at the edge. Since the angle formed by the surface facing the coming direction, that is, the rake angle α is less than 60 °, the toner on the image bearing member is removed by the edge as compared with the case of using a conventional cleaning blade having a large rake angle. By scooping more, it is possible to scrape more toner from the image carrier.

Further, in this cleaning device,
The rake angle α of the cleaning blade is set to be larger than the angle formed by the bottom of the toner when the toner is deposited on the horizontal surface (hereinafter referred to as “repose angle”). The friction coefficient of the toner is determined by the material and surface condition, and when the toner is piled up on a horizontal surface, the angle of repose becomes a constant value determined by the friction coefficient and particle size of the toner, regardless of the size of the pile. Then, even if new toner particles are placed on the slope of the mountain, the toner particles fall down along the slope due to gravity, and the hem angle is reproduced to a constant value.

Immediately before the toner is peeled off by the cleaning blade, the toner adheres to the image carrier, and the adhesive force is larger than the centrifugal force of the image carrier. Then, the toner is forcibly peeled off by the cleaning blade. Therefore, for a short period of time immediately after the toner is forcibly peeled off by the cleaning blade, a centripetal force toward the surface of the image bearing member acts on the toner by the difference between the adhesive force and the centrifugal force. The angle of repose above is the angle of the hem of the ridge when the toner is piled up on the horizontal plane where gravity acts, but the toner peeled off from the image carrier in this way also carries an image like gravity. A centripetal force acting on the surface of the body acts. Therefore, the conditions are the same as when the toner is piled up on the horizontal surface for a short period of time, and the toner piles having the hem of an angle of repose or more with respect to the surface of the image carrier cannot be formed. Therefore, by making the rake angle α larger than the angle of repose, the toner will slide down along the rake face of the edge, and a large amount of toner will not run on the rake face of the edge.

That is, in the present invention, the rake angle α is 6
By setting the angle to less than 0 °, the toner on the image bearing member is more scooped up by the edge, so that the toner can be scraped off more from the image bearing member, and the capsule is prevented from being broken when the capsule toner is used. On the other hand, by making the rake angle α larger than the hem angle described above, it is possible to prevent a large amount of toner from being deposited on the rake face of the edge. As a result, the surface of the image carrier can be cleaned more reliably. Thus, the toner scraped off the image carrier by the edge is promptly removed from the contact portion between the image carrier and the edge by an appropriate means.

[0016]

Embodiments (1) Configuration of Embodiments Embodiments according to the present invention will be described in detail below with reference to the drawings. First, FIG. 1 shows a first embodiment of the present invention.
It is a side view which shows the usage mode of the cleaning apparatus 13 of an Example. In this cleaning device 13, a plate spring 15 is fixed to a rigid mounting member 14c mounted on a rigid support portion 14a with a screw 14b. A surface of the cleaning blade 16 opposite to the photosensitive drum (image bearing member) 1 is bonded to the plate-shaped spring 15,
The cleaning blade 16 is supported by the plate spring 15. The material of the leaf spring 15 is, for example, SUS.
Steel plates, phosphor bronze plates, and other metal materials having spring characteristics are preferable, and the material of the cleaning blade 16 is
For example, a rubber material such as polyurethane having a hardness of about 77 ° (Hs), and a material having elasticity equivalent to this are suitable.

Also, in this embodiment, the edge 17
Surface of the contact portion when the photosensitive drum 1 is pressed against the surface of the photosensitive drum 1 in the rotation direction side, and the edge 17 facing the direction in which the photosensitive drum 1 rotates (rake surface) 17
The cleaning blade 16 has an angle (rake angle) α with a that is less than 60 ° and is larger than the angle (the angle of repose) formed by the hem of the ridge of the toner 2 when the toner 2 is deposited on a horizontal surface. And the edge 17 is formed.

Cleaning blade 1 used here
An example of No. 6 is shown in FIG. This cleaning blade 16
The rake face 17a is formed to be curved in a convex shape, and the face 17b opposite to the rake face 17a is a flat face. The edge angle θ of the edge 17 is smaller than the rake angle α at the time of press contact (see FIG. 1) and is in the range of 55 ° to 35 °. The cleaning blade 16 is brought into contact with the photosensitive drum 1 with a predetermined pressure contact force and is curved as shown in FIG. The rake angle α of the range can be created. The cleaning blade 1
The shape of 6 is not limited to that shown in FIG. 2, and even if the rake surface 17a is a flat surface or the opposite surface 17b is curved in a convex shape, the cutting edge angle θ falls within the above range. Can be used if present.

FIG. 3 shows another example of a cleaning blade 26. The rake face 26a of the cleaning blade 26 has a step shape on the most tip side, and has a flat shape on the base end side. The surface 17b opposite to the rake surface 17a is a flat surface. The edge angle θ of the cleaning blade 27 is also in the range of 55 ° to 35 °, and this blade 27 can be used in the embodiment as in the blade 17 shown in FIG.

Next, the angle of repose of the toner 2 will be described with reference to FIG. In the figure, the symbol β indicates the angle of repose. The friction coefficient of the toner 2 is determined by the material and surface condition. When the toner 2 is piled up on the horizontal plane H, the angle of repose, which is the angle of the hem, is the particle diameter and the friction coefficient of the toner 2 regardless of the size of the pile. It becomes a constant value determined by. Then, even if particles of the toner 2 are newly placed on the slope of the mountain, the particles of the toner 2 fall along the slope, and the hem angle is reproduced to a constant value. Thus, the angle of repose β is a value that differs depending on the type of toner 2, and is usually 1
It is in the range of 3 ° to 25 °. The type of toner 2 is selected according to the model of the image forming apparatus.

(2) Operation of Embodiment In this embodiment, after the toner 2 is transferred to a sheet (not shown) as the photosensitive drum 1 rotates, the photosensitive drum 1
The toner 2 remaining on the surface of the
6, edge 17 is reached. Then, the remaining toner 2
Are stopped by the edge 17 and are separated from the surface of the photoconductor drum 1, and at the same time, the photoconductor drum 1 is discharged. In this embodiment, the cutting edge angle θ is 55 ° to 3 °.
Since the rake angle α is set to less than 60 ° in the range of 5 °, the particles of the toner 2 on the photoconductor drum 1 are further removed by the edge 17 as compared with the case of using the conventional cleaning blade having a large rake angle. The toner 2 can be scraped off more from the photosensitive drum 1 by scooping up more.

Further, as described above, the cleaning blade 16 is manufactured from a rubber material such as polyurethane having a hardness of about 77 ° (Hs), which is a relatively high hardness, or other material having elasticity equivalent to this, and the cleaning blade 16 is manufactured. 16
Is supported by the plate-like spring 15, the cleaning blade 16 can be brought into contact with the photosensitive drum 1 with a sufficient pressure contact force. Therefore, even if the cutting edge angle θ is small,
It is possible to prevent the toner 2 from passing between the edge 17 and the photoconductor drum 1 or causing filming.

When the toner 2 is scraped, the particles of the preceding toner 2 are first dammed by the rake surface 17a of the edge 17 and separated from the surface of the photosensitive drum 1, and the particles of the subsequent toner 2 are sequentially raked. By reaching 17a, the particles of the preceding toner 2 are pressed and the rake face 17
get on a. In this case, immediately before the toner 2 is peeled off by the edge 17, the toner 2 is attached to the photosensitive drum 1 by charging, and the adhesive force is larger than the centrifugal force of the photosensitive drum 1. Then, the toner 2 is forcibly peeled off by the cleaning blade.

Therefore, for a short period of time immediately after the toner 2 is forcibly peeled off by the edge 17, the toner 2 is directed to the surface of the photosensitive drum 1 by the difference between the adhesive force and the centrifugal force due to the above charging. Your mind is working. The angle of repose β above is
The angle of the hem of the ridge when the toner 2 is piled up on the horizontal plane H on which gravity acts, the toner 2 peeled off from the photoconductor drum 1 in this way also has the photoconductor drum 1 like gravity. The centripetal force acting on the surface of For this reason, the conditions are similar to those in which the toner 2 is piled up on the horizontal surface for a short period of time, and the pile of the toner 2 having the hem of the angle of repose β or more cannot be formed on the surface of the photoconductor drum 1. Become.

As described above, by making the rake angle α larger than the repose angle β, the toner 2 is made to slide down along the rake face 17a of the edge 17, and the rake face 1
It is possible to suppress the amount of the toner 2 riding on the 7a. As shown in FIG. 1, in this embodiment, the edge 17 is pressed against the photosensitive drum 1 from the lateral direction, and the rake face 17a of the edge 17 is directed downward. After that, the toner 2 drops and is received by a toner processing device (not shown) below. In this way, the toner 2 reaching the contact portion between the edge 17 and the photosensitive drum 1 is scraped up by the rake face 17a of the edge 17, and then quickly separated without being deposited in a large amount on the contact portion. .

Therefore, the particles of the toner 2 attached to the photosensitive drum 1 and conveyed are accumulated on the contact portion between the edge 17 and the photosensitive drum 1, and the rake face 17a of the edge 17 is covered by the preceding toner 2. And subsequent toner 2
There is no problem that is removed. As a result, the preceding toner 2 is pressed by the succeeding toner 2 and the preceding toner 2 becomes the edge 1.
It is possible to perform reliable cleaning without passing between the photosensitive drum 1 and the photosensitive drum 1. Further, the toner 2 is prevented from being pressed against the photosensitive drum 1 by the edge 17 to cause filming. In particular, even when an encapsulated toner having a low mechanical strength is used as the toner 2, the outer core of the encapsulated toner is not crushed between the edge 17 and the photosensitive drum 1, and the inner core material is the photosensitive drum. No sticking to the surface of 1. As described above, according to the cleaning device of this embodiment, since reliable cleaning can be performed, the quality of the image formed by the image forming device can be improved.

By the way, the material of the cleaning blade 16 is a rubber material such as polyurethane and a material having elasticity equivalent to other rubber materials. However, these materials have large viscoelasticity and their elastic force changes depending on temperature. I will end up. Therefore, it is difficult to always obtain a constant pressure contact force only with the cleaning blade 16, but in this embodiment,
Since the cleaning blade 16 is supported by the metal plate spring 15, the property that the elastic force changes depending on the temperature of the cleaning blade 16 is compensated by the plate spring 15 whose elastic force does not change with temperature. You can This makes it possible to maintain a constant pressure contact force applied to the photosensitive drum 1 from the cleaning blade 16 even in an environment where the temperature varies greatly. Therefore, it is possible to prevent the toner 2 from entering between the edge 17 and the photosensitive drum 1, reduce the possibility of crushing the toner 2, and perform good cleaning.

Cleaning device 13 according to the above embodiment
Was manufactured and the actual pressure contact force was measured. In this experiment, in the cleaning device 13 shown in FIG.
Was a SUS steel material having a thickness of 0.10 mm and a length of 12.5 mm. The cleaning blade 16 has a hardness of 77 ° (H
In s), the length is 12 mm and the thickness is 2 mm, and the edge angle θ of the edge 17 of the polyurethane is 40 °.
Contact length l between the cleaning blade 16 and the plate spring 15
Was 4 mm, and the distance L from the fitting 14c to the tip of the cleaning blade 16 was 22 mm. And
After the cleaning blade 16 is brought into contact with the photosensitive drum 1 at a set angle of 22 ° (the angle between the edge 17 when not in pressure contact and the tangent plane of the surface of the photosensitive drum 1), the radius of the photosensitive drum 1 is further increased. Traveling distance inward (direction of bite)
As a result of pressing for 1.3 mm, the rake angle α was 57 °. As the photosensitive drum 1, a photosensitive drum having an organic photosensitive layer was used, and its diameter was 84 mm.

Then, the cleaning device 13 was mounted on a copying machine (not shown) as an image forming apparatus, and 3000 sheets of A3 size paper were copied at a processing speed of 105 mm / sec of the copying machine. Toner 2 used was a normal powder toner and a capsule toner. The peripheral speed of the photosensitive drum 1 at this time is also 105 mm / sec. The environmental conditions at that time were a room temperature of 22 ° C. and a humidity of 50%. In this experiment, no cleaning failure occurred, either with the powdered toner or with the capsule toner. Further, as a result of analyzing the capsule toner scraped off by the cleaning blade, the outer shell was found to be only slightly broken.

5 and 6 show experimental results for confirming the effect of supporting the cleaning blade 16 of the above-mentioned embodiment by the plate-shaped spring 15. In the experiment corresponding to FIG. 5, the supporting member such as the plate spring 15 is not used, and the conventional cleaning blade 6 shown in FIG.
The relationship between the biting amount and the pressure contact force when pressed against the photosensitive drum 1 was examined, and in the experiment corresponding to FIG. 6, the cleaning blade 16 was supported by the plate spring 15 and pressed against the photosensitive drum 1 as in the embodiment. Then, the bite amount was changed and the relationship between the bite amount and the pressure contact force was investigated. At that time, there were two environmental conditions: a room temperature of 5 ° C. and a humidity of 15%, and a room temperature of 45 ° C. and a humidity of 85%. The other experimental conditions were the same as above. Comparing these figures, the influence of temperature fluctuation is remarkable in FIG. 5, whereas the influence is extremely small in FIG. Therefore, obviously the plate spring 15
It was confirmed that it was possible to prevent the fluctuation of the pressure contact force due to the temperature fluctuation by using.

(3) Modification Example FIG. 7 is a side view showing a modification example of the above embodiment. As shown in FIG. 1, in the above-described embodiment, the cleaning blade 16 is pressed against the photosensitive drum 1 from the side, and the edge 17 faces downward of the cleaning blade 16, but in the modified example of FIG. The cleaning blade 16 is pressed against the photosensitive drum 1 from almost directly above, and the edge 1
7 is arranged almost directly beside the cleaning blade 16. Other configurations are the same as those in the above-mentioned embodiment. Even in this case, it can be used in the same manner as the above embodiment. The toner 2 separated at the edge 17
Are finally removed by an appropriate means (not shown).

[0032]

As described above, according to the present invention, the rake angle α of the edge of the cleaning blade is 6
Since the angle is less than 0 °, more toner is removed from the image bearing member by scooping up more toner on the image bearing member by the edge than when using a conventional cleaning blade with a large rake angle. it can. Further, since the rake angle is made larger than the repose angle of the toner, the centripetal force after peeling the toner from the rotating image carrier causes the toner once riding on the edge to slide down along the edge, and Of toner on the edges is prevented.

That is, in the present invention, the rake angle α is 6
By setting the angle to be less than 0 °, more toner can be scraped off from the image bearing member by scooping more toner on the image bearing member by the edge, while the rake angle α is larger than the above-mentioned hem angle. By doing so, the toner comes to slide down along the rake face of the edge, and it is possible to prevent a large amount of toner from riding on the rake face of the edge.

Therefore, the preceding toner is less likely to slip through between the edge and the image bearing member by being pressed by the succeeding toner, and reliable cleaning is performed. Also,
It is also prevented that the toner is pressed against the image carrier by the edge and causes filming. In particular, even when an encapsulated toner having low mechanical strength is used, the inner core material is fixed to the surface of the image bearing member without crushing the outer shell of the capsule toner between the edge and the image bearing member. Never. Since good cleaning can be performed in this way, the quality of the image formed by the image forming apparatus can be improved.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a cleaning device for an image forming apparatus according to the present invention.

FIG. 2 is a side view showing an example of a cleaning blade used in the embodiment.

FIG. 3 is a side view showing another example of the cleaning blade used in the embodiment.

FIG. 4 is a side view showing a state in which toner is raised on a horizontal surface.

FIG. 5 is a graph showing the results of examining the effect of temperature fluctuations in a conventional cleaning device that does not use a plate spring.

FIG. 6 is a graph showing the results of examining the influence of temperature fluctuations in a cleaning device of an example using a plate spring.

FIG. 7 is a side view showing a modification of the embodiment.

FIG. 8 is a side sectional view showing an example of a cleaning device of a conventional image forming apparatus.

FIG. 9 is a side view showing a main part of another example of the conventional cleaning device of the image forming apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 photoconductor drum (image carrier), 2 toner, 13 cleaning device, 14a supporting portion, 14b screw, 14
c Blade mounting bracket, 15 leaf spring, 16 cleaning blade, 17 edge, 17a rake face, α
Rake angle, β repose angle, θ cutting edge angle.

Claims (1)

[Claims] 1. A cleaning device of an image forming apparatus, comprising a cleaning blade provided with an edge which is brought into pressure contact with a surface of a rotating image elastic body to remove toner adhering to the surface, wherein the edge is used as the image carrier. The angle formed by the surface of the contact portion at the time of pressing in contact with the body on the rotational direction side of the image carrier and the surface of the edge facing the direction in which the image carrier rotates is less than 60 °, and the toner A cleaning device for an image forming apparatus, wherein the angle is larger than the angle formed by the hem of the mountain of the toner when the toner is deposited on a horizontal surface.