JPH07281510A - Image-forming device - Google Patents

Abstract

PURPOSE:To clean an electrifying means and a transfer means away from an image-forming body and to replace the electrifying means and the transfer means in a short time by intermittently retracting the electrifying means and the transfer means from the imageforming body. CONSTITUTION:Recording paper P to which a visible image 3A is transferred is subjected to fixing by means of a fixing device 15, and residual toner 3B on the surface of the photosensitive drum 1 is cleared away by a cleaner 5. As a recording operation is repeated in such a manner, the electrifying roller 2 and the transfer roller 4 used for electrification and transfer, respectively, in contact with the surface of the photosensitive drum 1 are soiled because the residal toner on the surface of the photosensitive drum 1 stick to them. Therefore, the electrifying roller 2 and the transfer roller 4 are cleaned while rotated at a low speed in contact with cleaning members 13 and 14, respectively, after the fixed recording operation is performed and the electrifying roller 2 and the transfer roller 4 are separated from the surface of the photosensitive drum 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a means for charging and transferring an image forming body in an image forming apparatus, particularly an electrophotographic apparatus.

[0002]

2. Description of the Related Art A photosensitive layer of an image forming body for forming an image is uniformly charged by a charging means, an electrostatic latent image is formed on the charged surface of an original and other image information by an exposing means, and the electrostatic latent image is formed. The toner is used to form a visible image on the image using developing means. A method of fixing the visible image on the recording paper by using the heat fixing means after transferring the visible image onto the recording paper by using a transfer means is an image forming apparatus, particularly a copying apparatus using an electrophotographic method. Widely used.

As the charging means and the transfer means, generally, a high voltage power source is applied to a thin metal wire, the photosensitive layer of the image forming body is charged by a corona discharge function, and the transfer means further forms toner. A means for transferring an image from the photosensitive layer to recording paper is used. In addition to the above-mentioned charging means and transfer means, means for charging and transferring by directly contacting with the photosensitive layer of the image forming body is used. As such means, for example, JP-A-2-272582. , The same 2-3093
No. 71 and No. 3-11373 are disclosed. The charging / transferring unit moves in the same direction as the moving direction of the image forming body while contacting the image forming body to perform charging or transfer. As described above, the means for contacting and charging or transferring is formed in the shape of a rotating roller or belt, and is configured to rotate while contacting with the movement (rotation) of the image forming body. JP-A-3-234458 is disclosed as means for roughening the roller surface or the belt surface in order to prevent uneven contact between the roller surface or the belt and the surface of the image forming body.

Since the roller- or belt-shaped charging and transfer means is always in contact with the image forming body, residual toner on the image forming body adheres to reduce charging efficiency. A cleaning member is provided in contact with the cleaning member, and is cleaned by the cleaning member according to the rotating operation of the charging and transfer means as described above. Japanese Patent Laid-Open No. 59-77467 discloses a method for effectively separating toner, which is not a cleaning means.
The separating means is a means for transferring the toner image formed on the image forming body by an intermediate transfer body having an adhesive material on the surface thereof, and the toner image is efficiently transferred to the intermediate transfer body.

[0005]

As described above, since the charging means and the transfer means for charging and transferring while always contacting the photoreceptor surface of the image forming body are in direct contact with the photoreceptor surface of the image forming body, The charge application efficiency is good, and a good image can be formed. However, since the photoreceptor of the image forming body is generally formed in a cylindrical shape or a belt shape, the charging means or the transfer means is formed in a small diameter cylindrical shape or belt,
The charging or transfer operation is performed while constantly rotating and making contact. Therefore, when the image forming body is rotating, the charging unit or the transfer unit is also rotating at the same time. At that time, as described above, the charging means or the transfer means is always in contact with the scraper means or the belt-shaped cleaning means for removing the toner, and the cleaning is performed. As described above, the charging unit or the transfer unit that rotates together with the image forming body,
Since the image forming member is rotated at the same speed as the peripheral speed of the surface, the cleaning unit and the rotating charging unit or transfer unit are contacted at high speed for cleaning.

Therefore, the surfaces of the charging means and the transfer means are not sufficiently cleaned, and a part of the surface is contaminated with toner, paper powder, etc., so that the electric resistance changes during charging and transfer. The change in the electric resistance has a drawback that uneven charging or transfer omission occurs on the surface of the image forming body, causing unevenness in the image formed on the recording paper.

Further, since the charging / transferring means is always in contact with the surface of the image forming body to carry out the charging / transferring operation as described above, the surface is abraded within a short period of time and the charging / transferring efficiency is lowered. Therefore, it is necessary to replace the charging unit and the transfer unit. However, it takes a lot of time and skill to remove the charging means and the transfer means from the main body of the apparatus and attach the new charging means and the transfer means, and further, the use of the image forming apparatus main body must be stopped at the time of the replacement. There are drawbacks such as not becoming.

The present invention was specifically conceived to remedy the aforementioned drawbacks. That is, the charging means and the transfer means, which are in contact with the surface of the image forming body, are separated from the surface of the image forming body at the time of kneading, and cleaning is performed using the cleaning means at the separated positions.

Further, the object is to replace the charging means and the transfer means in a short time.

[0010]

To achieve the above object, the present invention provides an image forming apparatus according to claim 1, which has a charging means and a transfer means for charging or transferring the image forming body. Then, the charging means and the transfer means are intermittently retracted from the image forming body, and brought into contact with a cleaning member for cleaning the charging means and the transfer means at the retracted operation position. 3. The charging means and the transfer means according to claim 2, wherein the charging means and the transfer means are composed of rotating members, and rotate at low speed while contacting the cleaning member at the retracting position. The cleaning member according to claim 3,
The cleaning unit is composed of a movable member, and when the charging unit and the transfer unit are brought into contact with each other, the charging unit and the transfer unit which rotate are brought into contact with the cleaning member at a relative speed. In claim 4, the retracting operation of the charging means and the transfer means from the image forming body is performed when the power of the image forming apparatus is turned on, when a specific number of recording sheets is completed, or after a specific image forming operation time has elapsed. thing. 6. The retracting operation of the charging means and the transfer means from the image forming body according to claim 5, wherein the retracting operation is performed by an image forming abnormality signal of the image forming apparatus. In claim 6,
In an image forming apparatus having a charging unit and a transferring unit for constantly charging or transferring the image forming body, a cleaning member for cleaning the charging unit and the transferring unit is intermittently provided on the charging unit and the transferring unit. Contact by moving and cleaning. 8. The charging means and the transfer means according to claim 7, wherein the charging means and the transfer means are composed of rotating members, and when contacting with the moving member, the charging means and transfer means rotate at a lower speed than during image formation. thing.
12. An image forming apparatus having a charging means and a transfer means for contacting an image forming body to charge or transfer the image forming body, wherein a cleaning member for adhering toner is brought into contact with the charging means or the transfer means. thing. 13. The cleaning member according to claim 12, wherein the cleaning member is an elastic member. 14. The cleaning member according to claim 13, wherein the cleaning member has a roll shape or a plate shape. 15. The cleaning member according to claim 14, wherein the cleaning member is cleaned by passing between the image forming body and the charging unit or the transfer unit. 16. The charging device according to claim 15, wherein the charging device and the transfer device are released from contact with the image forming body when being cleaned by the cleaning member. The image forming apparatus according to claim 16, further comprising a plurality of charging means and a transfer means, wherein the plurality of charging means and the transfer means are provided, the charging means and the transfer means contacting an image forming body to charge or transfer the image forming body. And the transfer means can be selectively brought into contact with the image forming body. 18. The charging device and the transfer device, which are in contact with the image forming member, among the plurality of charging devices and the transferring device are moved to a non-contact position from the image forming member and replaced by a rotation operation. thing. 19. The apparatus according to claim 18, wherein the plurality of charging means and the transfer means are replaceable at a position moved to a non-contact position with the image forming body. 20. The charging device and the transfer device according to claim 19, wherein the plurality of charging devices and the transfer device are cleaned by a cleaning member at a non-contact position with the image forming body. 21. The replacement operation of the plurality of charging means and transfer means according to claim 20, which is activated after completion of a specific number of recording sheets, after a specific recording operation time, or by an image formation abnormality signal of the image forming apparatus. Achieved by

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of an image forming apparatus using the charging / transferring means of the present invention and the cleaning means of the charging / transferring means. Reference numeral 1 is a photosensitive drum as an image forming body. A charging roller 2 which is rotatable and provided in contact with the rotation direction of the photosensitive drum 1, and a developing device 3.
And a transfer roller 4 rotatably and in contact with the photosensitive drum 1, and further, a cleaning device 5 for removing toner remaining on the surface of the photosensitive drum 1.
Is provided. Reference numeral 6 denotes a manuscript, which irradiates the manuscript 6 with an irradiation lamp 7 and reflects light of the manuscript 6 with a first reflecting mirror 8 which moves together with the irradiation lamp 7 and second and third reflecting mirrors 9 arranged in a V shape. , 10 through the focusing lens 11 to expose the surface of the photosensitive drum 1 charged by the charging roller 2 from the fourth reflecting mirror 12. Reference numeral 13 is a cleaning member for cleaning the charging roller 2, and is provided so as to come into contact with the cleaning member 13 at a position where the charging roller 2 is separated from the surface of the photosensitive drum 1.
Reference numeral 14 is a cleaning member for cleaning the transfer roller 4, and is provided so as to come into contact with the cleaning member 14 at a position where the transfer roller 4 is separated from the surface of the photosensitive drum 1. 15 is a fixing device, M ₁ is the photosensitive drum 1
A driving motor for driving the axes 1A, the drive motor M ₁ is controlled to rotate through the output device 17 from the CPU 16.

FIG. 1 is constructed as described above, and the photosensitive drum 1 is rotated in the arrow direction by the drive motor M ₁ from the CPU 16 via the output device 17. Photoconductor drum 1
Is rotated to give an electric charge by the charging roller 2 rotating at a relative speed to the surface of the photoconductor drum 1, and the image of the original 6 irradiated by the irradiation lamp 7 is exposed on the surface of the photoconductor drum 1 so as to be static. A latent image is formed. The electrostatic latent image is transferred to the developing device 3
To develop a visible image 3A. The visible image 3A is transferred onto a recording paper P fed from one side by a transfer roller 4 which rotates at the same speed as the surface of the photosensitive drum 1. Visible image 3
The recording paper P to which A has been transferred is fixed by the fixing device 15, and the toner 3B remaining on the surface of the photosensitive drum 1 is cleaned by the cleaning device 5.

When the recording operation is repeated as described above, the transfer roller 4 and the charging roller 2 which is in contact with the surface of the photosensitive drum 1 to perform charging and transfer are connected to the photosensitive drum 1.
The toner that remains on the surface adheres and becomes dirty. Therefore, after performing a certain recording operation, the charging roller 2 and the transfer roller 4 are separated from the surface of the photosensitive drum 1 and brought into contact with the cleaning members 13 and 14, and the charging roller 2 and the transfer roller 4 rotate at a low speed. While doing the cleaning.

2 and 3 show the rotation of the charging roller 2 and the transfer roller 4, and the operating mechanism during the cleaning operation. In Figure 2, the gear G ₁ in the axial 1A of the photosensitive drum 1 is fixed, the drive gear G ₂ of the gear G ₁ to the said charging roller 2, the driving gear G ₃ of the transfer roller 4 The charging roller 2 and the transfer roller 4 are configured to rotate together at a relative speed together with the photosensitive drum 1.
On the other hand, when the charging roller 2 and the transfer roller 4 are separated from the surface of the photosensitive drum 1, gears G ₄ and G ₅ for low speed rotation that mesh with the gears G ₂ and G ₃ are provided, and a drive motor for low speed rotation is provided. M ₂
Connect to. The drive motor M ₂ is connected to the CPU 16 via an output device 18. With the above-described structure, during normal recording operation, the CPU 16 drives the drive motor M ₁ via the output device 17 to rotate the photosensitive drum 1 and the gear G ₁ from the shaft 1A in the direction of the arrow. As described above, the surface of the photosensitive drum 1, the charging roller 2, and the transfer roller 4 rotate at a relative speed, and the surface of the photosensitive drum 1 is charged and the visible image 3A is efficiently transferred onto the recording paper P.

3 (a), 3 (b) and 3 (c) show an operating mechanism of the charging roller 2 or the transfer roller 4 and a cleaning means. FIG. 3 (a) shows the charging roller 2 Actuating lever 1
9 is provided at one end of the operating lever 19 and the other end of the operating lever 19 is provided with an operating cam
Set 0 and spring 21 spring. By the rotation of the actuating cam 20, for example, a drive motor (not shown),
The operating lever 19 is opened, and the charging roller 2 is separated from the surface of the photosensitive drum 1 by the spring 21 so as to contact the plate-shaped cleaning member 13. Figure 3
(b) shows a roller-like cleaning member 131 provided as a cleaning member, which rotates the charging roller 2 and
The roller-shaped cleaning member 131 is configured to use a reduction gear or the like in mutually opposite directions or to generate a speed difference,
Make sure to clean the transfer roller 2. Also, when contacting at a high speed, the contact should be made in the same direction. FIG. 3C shows a wave-shaped cleaning member 132 as a cleaning member.
Is provided, and the supply shaft 133 and the winding shaft 134 of the wave-shaped cleaning member 132 are sequentially moved for each cleaning. The other mechanism is similar to that shown in FIG. The transfer roller 4 also uses the above-mentioned operating mechanism.

At the time of power-on of the image forming apparatus configured as described above, after a certain number of recording sheets has elapsed, after a certain recording operation time has elapsed, or in the image forming means of the image forming apparatus, Provided with means for detecting current value or voltage value,
When an abnormality is detected, the CPU 16 stops the drive motor M ₁ via the output device 17 to stop the photosensitive drum 1. Next, the actuating cam 20 is actuated to activate the spring.
At 21, the charging roller 2 and the transfer roller 4 are moved to the cleaning position, and the gears G ₂ and G ₃ are meshed with the gears G ₄ and G ₅ for low speed rotation as described above. Next, it is controlled by the CPU 16 and drives the low speed drive motor M ₂ which is slower than the image forming time through the output device 18, rotates the charging roller 2 through the gears G ₁ and G ₂ , and rotates the gear G ₅ , G ₃ through transfer roller 4
Are rotated at low speed and cleaned by the cleaning means 13.

Alternatively, the cleaning operation may be started by visually observing the image and pressing the cleaning operation button when an image defect occurs.

FIG. 4 shows a modification of the embodiment shown in FIG.
The means for cleaning the charging roller 2 and the transfer roller 4 by moving the cleaning means is shown. Since the basic structure of this embodiment is similar to that of FIG. 1, the description thereof will be omitted.

As described above, for example, when a certain number of recordings have been completed, the CPU 16 stops the drive motor M ₁ .
Next, controlled by the CPU 16, the plate-like cleaning members 1311 and 1312 are moved to the positions shown in the drawing by operating means via the output devices 22 and 23, and brought into contact with the charging rollers 2 and 4, respectively. Next, the CPU 16 rotates the drive motor M ₁ at a lower speed than the recording operation, and rotates the photosensitive drum 1 via the shaft 1A at a lower speed than that during image formation. By the rotation operation, the charging roller 2 in contact with the surface of the photosensitive drum 1 and the transfer roller 4 also rotate at a low speed, and are cleaned by the cleaning members 1311, 1312. After the photosensitive drum 1 is rotated by the drive motor M ₁ by the CPU 16 to complete the cleaning, the cleaning devices 1311 and 1312 are separated from the charging roller 2 and the transfer roller 4 by the output devices 22 and 23 by appropriate driving means. Let

FIGS. 5A, 5B and 5C show the drive mechanism for the cleaning members 1311, 1312 shown in FIG. In FIG. 5A, the cleaning member 1311 is provided at one end of the operation lever 191, and the operation cam 201 is provided at the other end of the operation lever 191 and the spring 211 is elastically held. Now, when the power of the image forming apparatus configured as described above is turned on, after a certain number of recording sheets has elapsed, after a certain recording operation time has elapsed, or as described above, the image forming of the image forming apparatus is performed. When an abnormality occurs in the means, the CPU 16 stops the drive motor M ₁ via the output device 17 to stop the photosensitive drum 1. Then, the actuating cam is rotated, for example, by a driving motor (not shown) against the spring 211 to bring the cleaning member 1311 into contact with the charging roller 2. In this state, the photosensitive drum 1 is again rotated in the direction of the arrow by the drive motor M ₁ at a lower speed than at the time of image formation, the charging roller 2 is rotated at the same time, and the cleaning member 1311 performs cleaning. After the cleaning is completed, the actuating cam 201 is rotated to release the cleaning member 1311 from the charging roller 2 by the spring 211. FIG. 5B shows an embodiment in which a roller-shaped cleaning member 135 is provided instead of the cleaning member 1311. FIG. 5C shows the cleaning member 131.
A cleaning member 136 in the form of a wave is provided in place of 1, 135, and a supply shaft 137 of the cleaning 136 in the form of a wave is provided.
And the take-up shaft 139 sequentially move each cleaning, and the pressing member 138 provided at the tip of the operating lever 19 moves the wave-like cleaning member 136 to the operating cam 201.
Is rotated to contact the charging roller 2. After the cleaning is completed, the operation lever 191 is released by the rotation of the operation cam 201 and the spring 211.

FIG. 6 shows a small printer device 300 of the image forming apparatus, for example, an upper frame 3001 and a lower frame 3002.
In this embodiment, a charging means for contacting the surface of the photoconductor drum to be charged and a transfer means for transferring the toner image are provided. A charging roller 302 centering on the photosensitive drum 301, an exposure device 303 using a laser beam, a developing device 304, a transfer roller 305,
A cleaning device 306 for the photosensitive drum 301 is provided, and the photosensitive drum 301, the charging roller 302, the developing device 304, and the cleaning device 306 are provided in the upper frame body 30.
A unit 307 integrated in 01 is provided so as to be detachable from the printer device 300. 308 is the lower frame 30
The recording paper P is fed between the photosensitive drum 1 and the transfer roller 305 by the paper feed roller provided on 02, and after the image is transferred by the transfer roller 305, the image is recorded by the fixing device 309. The recording sheet P is fixed on the sheet P, discharged by the transport roller 311, and the recording sheet P is discharged on the sheet discharge tray 312. Reference numeral 310 is a support shaft for opening the upper frame body 3001 and the lower frame body 3002.

FIG. 7 is a diagram in which the upper frame 3001 of the small printer 300 shown in FIG. 6 is opened around the support shaft 309, and the unit 307 can be taken out of the machine by opening. By taking out the unit 307 as described above, the charging roller 302 and the transfer roller 305 can be exposed to the outside as shown by arrows 313 and 314.

8A and 8B show a cleaning member 315 for cleaning the charging roller 302 or the transfer roller 305 shown in FIG. The cleaning member 315 is formed in a cylindrical shape in which a base 316 made of a metal or a resin material is covered with an adhesive member 318 made of a silicone type or a fluorine type rubber on the outside through an elastic member 317 made of a rubber or sponge material. .

FIGS. 9A and 9B show an embodiment in which the cleaning member 315 shown in FIG. 8 is attached to the operation frame body 319 to facilitate the cleaning operation and the cleaning operation is shown. Holding portions 320 and 321 are formed in a part of the operation frame body 319. Then, the fingertip 322 holds the holding portion 32 of the operation frame body 319.
While holding the ends of 0 and 321, the cleaning member 302 is pressed against the charging roller 302 or the transfer roller 305 along the arrow 313 or the arrow 314 as shown in FIG. 7, and is moved to the right or left as shown in the figure. While performing the cleaning operation. The cleaning member 315 is a charging roller 302 or a transfer roller as shown in the figure.
Cleaning is performed while contacting the 305 in a parallel position or in a right angle direction.

FIGS. 10A and 10B show another cleaning method for the transfer roller 302 or the transfer roller 305. FIG. 10 (a) is a silicone-based cleaning member 315 shown in FIG.
Alternatively, as shown in FIG. 10A, a belt-shaped cleaning member 400 having an adhesive surface made of fluorine-based rubber formed on one surface is sandwiched between the surface of the photosensitive drum 1 and the charging roller 302. that time,
By disposing the adhesive surface on the charging roller 302 side and pulling one end of the belt-shaped cleaning member 400 with the fingertip 401 in the direction of the arrow, the charging roller 302 rotates and the belt-shaped cleaning member 4
Paper dust, toner, etc. adhere to the adhesive surface of 00 and are cleaned. During cleaning, the photosensitive drum 1 is slightly separated from the belt-shaped cleaning member 400. In FIG. 10 (b), the belt-shaped cleaning member 400 is automatically rotated by sandwiching the belt-shaped cleaning member 400 between the surface of the photoconductor drum 1 and the charging roller 302 and rotating the photoconductor drum 1 in the direction shown by the arrow. The charging roller 302 is rotated at the same time, and the charging roller 302 is also cleaned. In this case, by forming the adhesive surfaces on both sides of the belt-shaped cleaning member 400, the rotational force of the photosensitive drum 1 can be transmitted to the belt-shaped cleaning member 400, and the charging roller 302 can also be smoothly cleaned.

FIG. 11 shows another charging means and transfer means for the charging rollers 2 and 302 and the transfer rollers 4 and 305. The means fixes a support body 600 having arms formed in three directions to a pivotally provided shaft 604, and the support body 600 has three arms on each arm.
Individual charging rollers 601, 602, 603 are provided. Then, the charging roller 601 is brought into contact with the surface of the photosensitive drum 1 to apply an electric charge. When the charging roller 601 is used, for example, when a certain number of recording sheets or a certain recording operation time has elapsed, the charging roller 601 is separated from the surface of the photosensitive drum 1 in the direction of the arrow and then supported by the shaft 604. Rotate the body 600 to move to the next charging roller
Replace with 602 and contact the surface of the photosensitive drum 1.

FIGS. 12 (a), 12 (b) and 13 show another embodiment of the transfer and charging means of FIGS. 1, 7 and 11 above. FIG. 12 (a) shows that the shaft 703 rotatably provided has a support member.
700 is fixed, and charging rollers 701 and 702 are provided on both ends of the support 700.
Is provided, the charging roller 701 is brought into contact with the surface of the photosensitive drum 1,
Charge is applied. After recording a certain number of sheets as described above, the support 700 is rotated by the shaft 703, and the charging roller 70 is rotated.
Replace with 2, and contact the surface of the photosensitive drum 1. In FIG. 12B, a supporting body 800 is fixed to a rotatable shaft 803, charging rollers 801 and 802 are provided at both ends of the supporting body 800, and one charging roller 801 is provided.
Is brought into contact with the surface of the photosensitive drum 1, and the other charging roller 802 is brought into contact with the plate-shaped cleaning member 804. The charging roller 802 is used for charging for a certain period of time, and is rotated at a low speed by a separately provided rotating means (not shown) to perform cleaning by the cleaning member 804.
Then, the charge is applied to the surface of the photosensitive drum 1. Then, after the charging roller 801 has been used for a certain number of recorded sheets, the support 800 is rotated by the shaft 803 to bring it into contact with the plate-shaped cleaning member 804, and is rotated at a lower speed than the image forming time by using the rotating means. Then, cleaning is performed, and the charging roller 802 is brought into contact with the surface of the photosensitive drum 1 to apply electric charges. FIG. 13 shows FIG.
This is an example in which the cleaning means in (b) and a separate cleaning means are used. Belt-shaped cleaning member 900
Are provided on the supply shaft 901 and the winding shaft 902, respectively, and the belt-shaped cleaning member 900 is stretched at a fixed position by a pressing member 903. As shown in FIG. 12B, charges are alternately applied to the surface of the photosensitive drum 1 by the charging rollers 801, 802, and cleaning is performed by the belt-shaped cleaning member 900.
The belt-shaped cleaning member 900 sequentially winds the used portion on the winding shaft 902 according to the number of times of use. Further, the charging roller 60
When the 1,602,603,701,702,801,802 are moved to the cleaning position, the new charging roller can be easily replaced. Further, the charging means, the transfer means and the cleaning means of the present invention can be used for the belt photoreceptor. Further, although the embodiment of the charging means has been described with reference to FIG. 10, FIG. 11, FIG. 12, and FIG. 13 above, it goes without saying that the transfer means can also be used.

In the low-speed driving for cleaning the charging means or the transfer means, when the rotation speed is high, the toner filming increases, and when the rotation speed is low, the cleaning property deteriorates. A speed of about 1/10 is preferable.

[0029]

As described above, according to the present invention, the charging member for charging and transferring by contacting the surface of the photosensitive drum in the image forming member, and the transfer member, the operating time of the image forming apparatus or the number of recordings, etc. When the charging is completed, the cleaning means cleans the charging member and the toner, paper powder, etc. adhering to the transfer member, and the charging means and the transferring means keep the photosensitive drum at a normal value. Can be charged. Therefore, the charge becomes less than the normal value due to the adhesion of the toner, the paper powder, and the like, and uneven charging and transfer omission do not occur, and it is possible to always form an excellent image.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram in which a cleaning unit of the present invention is used in an image forming apparatus.

FIG. 2 is a configuration diagram showing a drive mechanism of the charging and transfer means of the present invention.

FIG. 3 is a configuration diagram showing an operation mechanism of a charging and transfer means of the present invention.

FIG. 4 is an overall configuration diagram of another embodiment in which the cleaning means of the present invention is shown in the image forming apparatus.

FIG. 5 is a configuration diagram showing a drive mechanism of a cleaning unit in FIG.

FIG. 6 is an overall configuration diagram in which the charging and transfer means of the present invention is used in another image forming apparatus.

7 is a configuration diagram of a state in which an image forming unit is removed from the image forming apparatus of FIG.

FIG. 8 is an overall view showing another cleaning member in the present invention.

9 is an overall view showing a state in which the cleaning member of FIG. 8 is used.

FIG. 10 is a configuration diagram showing another cleaning member in the present invention.

FIG. 11 is a configuration diagram showing another charging and transfer means of the present invention.

FIG. 12 is a configuration diagram showing another charging / transferring unit and a cleaning unit according to the present invention.

FIG. 13 is a configuration diagram showing the charging and transfer means of FIG. 12 and another cleaning means.

[Explanation of symbols]

1,301 Photosensitive drum 2,302,601,602,603,701,702,801,802 Charging roller 4,305 Transfer roller 13,14,131,132,1311,1312,135,136,135,400,
804,900 Cleaning member

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G03G 21/10

Claims (20)

[Claims] 1. An image forming apparatus having a charging means and a transfer means for charging or transferring the image forming body in contact with the image forming body, wherein the charging means and the transferring means are intermittently retracted from the image forming body, An image forming apparatus characterized in that it is brought into contact with a cleaning member for cleaning the charging means and the transfer means at the retracting position. 2. The image forming apparatus according to claim 1, wherein the charging unit and the transfer unit are composed of a rotating member and rotate at a low speed while being in contact with the cleaning member at the retracting position. 3. The cleaning member is composed of a movable member, and when contacting the charging unit and the transfer unit, the rotating charging unit and the transfer unit contact the cleaning member at a relative speed. The image forming apparatus according to claim 1. 4. The retracting operation of the charging unit and the transfer unit from the image forming body is performed when the image forming apparatus is powered on, when a specific number of recorded sheets is completed, or after a specific image forming operation time has elapsed. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. 5. The image forming apparatus according to claim 1, wherein the retracting operation of the charging unit and the transfer unit from the image forming body is activated by an image formation abnormality signal of the image forming apparatus. 6. An image forming apparatus having a charging unit and a transfer unit for constantly charging or transferring the image forming body, and a cleaning member for cleaning the charging unit and the transferring unit, the charging unit and the transferring unit. An image forming apparatus characterized by intermittently moving and contacting a cleaning means. 7. The charging unit and the transfer unit are composed of a rotating member, and when contacting the moving member in contact with the moving member, the charging unit and the transfer unit rotate at a lower speed than during image formation. The image forming apparatus according to claim 6, which is characterized in that. 8. The cleaning member is composed of a movable member, and when contacting the charging unit and the transfer unit, the rotating charging unit and the transfer unit contact the cleaning member at a relative speed. The image forming apparatus according to claim 6. 9. The contact operation of the charging unit and the transfer unit of the cleaning member is performed when an image forming apparatus is powered on.
7. The image forming apparatus according to claim 6, which is performed when a specific number of recorded sheets is completed or after a specific image forming operation time has elapsed. 10. The image forming apparatus according to claim 6, wherein the contact operation of the charging unit and the transfer unit of the cleaning member is activated by an image formation abnormality signal of the image forming apparatus. 11. An image forming apparatus having a charging means and a transfer means for contacting an image forming body to charge or transfer the image, and a cleaning member for adhering toner is brought into contact with the charging means or the transfer means. A characteristic image forming apparatus. 12. The image forming apparatus according to claim 11, wherein the cleaning member is an elastic member. 13. The image forming apparatus according to claim 11, wherein the cleaning member is formed in a roll shape or a plate shape. 14. The image forming apparatus according to claim 11, wherein the cleaning member performs cleaning by passing between the image forming body and the charging unit or the transfer unit. 15. The image forming apparatus according to claim 11, wherein the charging unit and the transfer unit release contact with the image forming body when being cleaned by the cleaning member. 16. An image forming apparatus having a charging means and a transfer means for contacting an image forming body to charge or transfer the image forming body, the image forming apparatus having a plurality of the charging means and the transfer means, the plurality of charging means and the transfer means. An image forming apparatus, wherein the means can be selectively brought into contact with the image forming body. 17. Among the plurality of charging means and transfer means, the charging means and the transfer means that are in contact with the image forming body are moved from the image forming body to a non-contact position by a rotation operation to be replaced. 17. The image forming apparatus according to claim 16, which is characterized in that. 18. The plurality of charging means and transfer means,
17. The image forming apparatus according to claim 16, wherein the image forming apparatus is replaceable at a position where the image forming body has moved to a non-contact position. 19. The charging means and the transfer means,
19. The image forming apparatus according to claim 16, wherein the image forming apparatus is cleaned by a cleaning member at a non-contact position with the image forming body. 20. The replacement operation of the plurality of charging means and transfer means is activated after completion of a specific number of recording sheets, after a specific recording operation time, or by an image formation abnormality signal of the image forming apparatus. The image forming apparatus according to claim 16 or 17.