JPH07110640A - Image forming device - Google Patents

Abstract

PURPOSE:To simplify the constitution of a contact electrostatic charging member cleaning means and to reduce the size of the device by relatively moving and bringing a cleaning member and a contact electrostatic charging member into a contact state and cleaning the contact electrostatic charging member for a specific time. CONSTITUTION:In every electrostatic charging roller cleaning period set previously in a control part, a light irradiating means 30 is moved to outside a 1st and a 2nd spider to being into contact with the electrostatic charging roller 2 of a cleaning pad 4 associatively with the moving operation, and the electrostatic charging roller 2 is cleaned intermittently. Thus, the light irradiating means 30 which is originally arranged in the image forming device is used in common as the control means of the cleaning pad 4 for the electrostatic charging roller 2 to make the mechanism constitution of the cleaning means for the electrostatic charging roller simpler than that when a dedicated mechanism like a solenoid is arranged; and a much arrangement space is not required, and the device is reduced in size and cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process of electrifying an image carrier such as an electrophotographic photosensitive member or an electrostatic recording dielectric such as an electrophotographic copying machine, a laser beam printer, an electrostatic recording device or the like. The present invention relates to an image forming apparatus that forms an image by an image forming process including the image forming process.

More specifically, the present invention relates to an image forming apparatus using contact charging means as a charging processing means for an image carrier.

[0003]

2. Description of the Related Art Conventionally, in this type of image forming apparatus,
A corona charger using corona discharge has been widely used as a charging means for the image carrier. The corona charger applies a high voltage (or a high current) to the corona wire to ionize the molecules in the air to attach a negative charge (or a positive charge) to the surface of the image carrier and charge it. It is a means.

However, the corona charger is expensive due to the application of a high voltage (high current), which produces a lot of undesirable corona discharge products such as O ₃ (ozone) and NOx (nitrogen oxide) at the same time as the corona discharge. Need a high voltage power supply,
There are many problems such as poor power efficiency.

Therefore, recently, a conductive member such as a roller body (charging roller) is used as a charging member and brought into direct contact with an image carrier as a member to be charged, and a DC voltage or a DC voltage and an AC voltage are applied to the charging member. A contact charging means (for example, Japanese Patent Laid-Open Nos. 63-149668 and 63-149669) for charging the surface of the image bearing member to a predetermined polarity and potential by applying a charging bias of the superposed oscillating voltage is used. It's starting to happen.

This contact charging means is substantially free of generation of corona discharge products such as O ₃ and can lower the power supply voltage.
It has features such as high power efficiency and energy saving without consuming a large amount of discharge energy.

[0007]

In the contact charging means, the contact charging member such as the charging roller which is brought into direct contact with the image bearing member as the member to be charged is durable in itself and has a long life which can be repeatedly used for a long time. It is a member, but during repeated use, the developer (toner) on the image carrier that has been removed by the image carrier cleaner, scattered developer from the developing section, paper dust from the transfer paper, etc. Foreign matter such as dust and dust from the outside adheres and gradually accumulates and becomes dirty, and a charging failure due to the dirt occurs.

Therefore, a cleaning member such as a cleaning pad for removing stains on the contact charging member is provided. When the cleaning member is provided so as to be in constant contact with the contact charging member, the cleaning ability of the cleaning member is contacted. Since it is difficult to maintain the life of the charging member, a contact control means for the cleaning member with respect to the contact charging member is provided, and the contact control means causes the cleaning member to contact the contact charging member for a proper time at an appropriate time. Cleaning of the contact charging member is performed by intermittently controlling the contact of the cleaning member with respect to the contact charging member so as to keep the contact charging member in a non-contact state at other times. It is designed to be durable.

A link mechanism using a solenoid is used as the contact control means, but this mechanism causes a sudden sound when the solenoid is operated, takes up space in the arrangement, and contributes to an increase in the cost of the apparatus. There was a problem such as.

Further, a solenoid as a driving means for moving the cleaning member toward and away from the contact charging member is arranged only on one end side in the longitudinal direction or the front side of the cleaning member due to an arrangement space and the like. The one-sided drive type installed, when the cleaning member is brought into contact with the contact charging member by the solenoid, causes the cleaning member to bend so that the cleaning member contact pressure is not evenly applied in the longitudinal direction of the contact charging member. There is a problem that cleaning failure occurs in the contact charging member portion where the contact pressure is not applied or the contact charging member portion where the contact pressure is weak.

Similarly, the present invention intends to make the cleaning member durable by intermittently controlling the contact and separation of the cleaning member with respect to the contact charging member, but solves the above problems.

[0012]

The present invention is an image forming apparatus having the following configuration.

(1) In the image forming apparatus using the contact charging means as the charging processing means for the image bearing member, a cleaning member for the contact charging member contacting the image bearing member is provided to control the position movement according to the image forming conditions. The movable image forming process means is controlled to move a predetermined position for a predetermined time at every contact charging member cleaning time calculated by the control system, and is interlocked with the movement of the means, and the cleaning member and the contact charging member. The image forming apparatus is configured to perform cleaning of the contact charging member for a predetermined time by moving the and from relative to each other in the contact direction from the non-contact state to bring them into contact with each other.

(2) A light-emitting body, in which the movable image forming process means removes electric charges charged in an image carrier portion other than the recording image area in the electrostatic charge image formed on the image carrier, and Either one or both of the light flux regulating members of the light emitter is a light irradiating unit whose position movement is controlled according to the magnification of the formed image, and the light irradiating unit is provided for each contact charging member cleaning time calculated by the control system. Contact charging member by moving the cleaning member and the contact charging member relative to each other in a contact direction from a non-contact state by moving the cleaning member and the position of the light irradiation unit for a predetermined time in association with the movement of the light irradiation unit. The image forming apparatus according to (1), characterized in that the cleaning is performed for the predetermined time.

(3) The movable image forming process means is an image forming means for image light onto the image carrier, the position movement of which is controlled according to the magnification of the formed image, and the image forming means is controlled by a control system. At each calculated cleaning time of the contact charging member, the cleaning member and the contact charging member are moved relative to each other in the contact direction from the non-contact state by moving the position for a predetermined time and interlocking with the movement of the means. The image forming apparatus described in (1) is characterized in that the contact charging member is cleaned for a predetermined time by bringing it into a contact state.

[0016]

That is, according to the present invention, as the contact control means of the cleaning member with respect to the contact charging member, a dedicated mechanism such as a link mechanism using a solenoid is not provided, but is originally provided in the image forming apparatus. A movable image forming process means whose position movement is controlled according to image forming conditions;
For example, in the electrostatic charge image formed on the image carrier, either one or both of a light emitter and a light flux regulating member of the light emitter for removing charges charged in the image carrier portion other than the recording image area are formed. Focusing on the light irradiating means whose position is controlled to move according to the image magnification, and the image moving means for moving the image onto the image carrier, which is controlled to move according to the image magnification,
This is calculated for each contact charging member cleaning time calculated by the control system,
The contact charging member is cleaned by moving the cleaning member and the contact charging member relative to each other in the contact direction from the non-contact state by interlocking with the movement of the member for a predetermined time and interlocking with the movement of the member. By executing the cleaning for the predetermined time, it also serves as contact control means of the cleaning member with respect to the contact charging member.

Therefore, as compared with the case where a dedicated mechanism such as a link mechanism using a solenoid is provided as the contact control means of the cleaning member with respect to the contact charging member, the mechanism structure of the contact charging member cleaning means is simplified, and It is possible to reduce the size and cost of the device without taking up the installation space. There is no problem of a sudden sound generated when the solenoid is operated unlike the link mechanism using the solenoid. Further, with a simple mechanism configuration, it is possible to bring the cleaning member and the contact charging member into contact with each other at a predetermined pressure evenly along the length by the means configuration that does not take up an installation space. It is possible to secure and maintain a good cleaning state of the contact charging member without causing cleaning failure due to uneven contact pressure.

[0018]

【Example】

<Embodiment 1> (FIGS. 1 to 5) FIG. 1 is a schematic configuration diagram of an image forming apparatus as an embodiment. The image forming apparatus of this example is an optical system moving type copying machine using a transfer type electrophotographic process.

Reference numeral 1 denotes a drum type electrophotographic photosensitive member (hereinafter referred to as a photosensitive drum) as an image bearing member, which is rotationally driven in a clockwise direction indicated by an arrow at a predetermined peripheral speed (process speed).

Reference numeral 2 denotes a charging roller as a contact charging member, which comprises a core metal 2a and a medium resistance rubber layer 2b concentrically formed on the outer periphery of the core metal in a roller shape. Are abutted against each other to rotatably support the bearing, and are rotated by the rotation of the photosensitive drum 1. The charging roller 2 may be rotationally driven by a drive system. Reference numeral 3 is a power source for applying a charging bias to the charging roller 2.

A cleaning pad 4 as a cleaning member for the charging roller 2 is attached to and supported by a spring plate member 38 as a supporting member. As will be described later, the cleaning pad 4 is intermittently controlled to contact the charging roller 2 to clean the outer peripheral surface of the charging roller 2.

In the course of rotation of the photosensitive drum 1, the charging roller 2 to which a predetermined charging bias is applied is uniformly primary-charged to a predetermined polarity and potential, and then at the exposure position 5, an original image is formed by an optical system described later. Slit exposure L
By receiving the image, an electrostatic charge image corresponding to the original image is formed.

The electrostatic charge image is developed as a toner image by the developing device 6, and the toner image is transferred to the transfer nip portion 8 which is the pressure contact portion between the photosensitive drum 1 and the transfer roller 7 as the transfer means. The image is transferred to the transfer paper (transfer material) P that has been fed to. Reference numeral 9 is a transfer bias application power source for the transfer roller 7.

A transfer paper cassette 10 is driven by a paper feed signal to drive a paper feed roller 11, and one transfer paper P in the cassette 10 is fed out in cooperation with a separating means. It is fed to the transfer nip portion 8 at a predetermined timing.

The transfer sheet P that has passed through the transfer nip portion 8 is separated from the photosensitive drum 1 and is conveyed and introduced into the fixing device 15 by the conveying means 14 to be subjected to the fixing process of the toner image and discharged as an image formed product (copy) as a discharge roller. Pair 16 to output tray 17
Is discharged to.

After the transfer of the toner image onto the transfer paper P, the surface of the photosensitive drum 1 is cleaned by a cleaning device 13 to remove adhered contaminants such as transfer residual toner, and is repeatedly used for image formation.

Reference numeral 21 denotes a fixed original platen glass, on which an original O is placed with an image surface to be copied facing downward with a predetermined placing reference, and an original pressure plate 21a is placed thereon to set. 22 is a document illumination lamp, 23 is a moving first mirror, 2
Numerals 4 and 25 are movable second and third mirrors, 26 is an imaging lens, and 27 to 29 are fixed first to third mirrors.

Document illumination lamp 22 and moving first mirror 2
3. Moving The second and third mirrors 24 and 25 are on standby below the document table glass 21 with the position indicated by the solid line on the left side of the glass 21 as the home position, and the document illumination lamp 22 and the movement are moved by the start signal. The first mirror 23 moves leftward along the lower surface of the platen glass 21 at a speed of V, and the moving second and third mirrors 24 and 25 also move leftward at a speed of V / 2. The downward image surface of the document O placed on the document table glass 21 is sequentially illuminated and scanned from the left side to the right side, and the reflected light on the document surface of the illumination light is reflected by the mirrors 23, 24, 25. The slit charge L is applied to the surface of the photosensitive drum 1 at the exposure position 5 through the imaging lens 26 and the mirrors 27, 28 and 29, so that the electrostatic charge corresponding to the original image is formed on the surface of the photosensitive drum 1 as described above. The image is formed .

Document illumination lamp 22 and moving first mirror 2
3. Moving When the second and third mirrors 24 and 25 reach the predetermined forward movement end points, they move back and return to their original home positions.

The position of the imaging lens 26 is controlled by a drive mechanism (not shown) to a variable power position corresponding to the selected copy magnification.

A blank lamp 31 (a, 30) serves as a light emitter for a portion of the surface of the photosensitive drum other than the recording image area in the electrostatic charge image formed on the photosensitive drum 1 serving as an image carrier.
b) and a reflecting mirror 32 (a, b) for controlling the light flux, a blank exposure B is performed, and a light irradiating means (blank exposing means) for removing unnecessary electric charges charged in that portion.

FIG. 2 is a perspective view of the light irradiation means 30, FIG.
FIG. 3 is an explanatory diagram of an operation and an irradiation range (blank exposure range).

In the image forming apparatus of this embodiment, image formation on the photosensitive drum 1 and conveyance of the transfer paper P are performed based on a so-called center reference. In FIG. 3, A-A is the central reference line.

In such a central reference apparatus, in the case of the image forming mode of reduction magnification, as shown in FIG. 3, the reduced image area formed on the surface of the photosensitive drum 1 based on the central reference is set in the front side. A non-image area is formed on the surface side of the photosensitive drum on the back side, and the non-image area is left with the primary charge charged by the charging roller 2, and if the development is continued, the non-image area is entirely covered. The developer (toner) adheres to the toner and is wasted. The light irradiating means 30 is means for erasing the unnecessary charges in the non-image area by light irradiation (blank exposure) before transferring to development.

Reference numerals 31a and 32a denote a first blank lamp as a light emitter and a first reflector as a light flux regulating member for blank exposure B of the non-image area on the front side.
Reference numerals 31b and 32b denote a second blank lamp as a light emitter and a second reflector as a light flux regulating member for blank exposure B of the non-image area on the back side.

Reference numerals 33a and 33b are first and second sliders on the front side and the back side, respectively, as support members to which the first and second blank lamps 31a and 31b are attached and supported, respectively. The second sliders 33a and 33b are provided on the housing 39 of the light irradiating means 30 with a long hole 41.
By means of the pin 42, the photosensitive drum 1 is arranged so as to be slidable and movable in the axial direction of the photosensitive drum 1 in the direction opposite to the axial direction.

Then, the first and second sliders 33a
The rack tooth portions 34a and 34b are respectively inwardly provided on 33b.
The rack tooth portions 34a and 34b are opposed to each other with the pinion gear 35 sandwiched therebetween and meshed with the pinion gear 35.

The pinion gear 35 is driven in the forward and reverse directions by a stepping motor 36 as a drive source mounted and supported on the lower surface side of the housing 39, and the first and second sliders 33a and 33b are linked to the pinion gear 35 in the forward and reverse directions.
That is, the first and second blank lamps 31a31b are moved in the axial direction of the photosensitive drum 1 in a direction in which the gap is widened and in a direction in which the gap is sandwiched.

The first and second reflectors 32a and 32b as light flux regulating members are fixedly arranged in the housing 39.

The first and second sliders 33a and 33b are normally set to the home position H at the position shown by the solid line in FIG.
Is held in a standby state. In the reduction magnification image forming mode, the stepping motor 36 is controlled by a control unit (not shown) so that the first and second sliders 33a and 33b are spaced from each other according to the reduction magnification of the formed image. The position is moved by a predetermined amount.

That is, the first and second sliders 33a, 33
The first and second blank lamps 31 respectively disposed in b
By a.31b, the non-image area generated on the front side portion and the back side portion of the surface of the photosensitive drum 1 according to the reduction ratio of the formed image is controlled to move to a predetermined amount position where the blank exposure B is performed and the charge is removed in the entire width. .

The light fluxes emitted from the first and second blank lamps 31a and 31b as light emitters are respectively the first and second reflection plates 32a as light flux regulating members as shown in FIG.
The light path is reflected by 32b, and its optical path goes straight toward an apparent position 1'where the photosensitive drum 1 is moved with the extension line C of the reflecting surface of the reflecting plate as the axis of symmetry.

In this way, in the image forming mode of the reduction magnification, the first and second blank lamps 31a and 31b and the first and second reflecting plates 32a and 32, which have been appropriately moved, are moved.
By b, the blank exposure B is performed on the non-image area generated in the front side portion and the back side portion with the reduced image area of the photosensitive drum 1 in the middle, and the non-image area is discharged.

The first and second sliders 33a and 33b are then returned to their original home positions H and stand by.

The first and second reflectors 32a and 32b as light flux regulating members are respectively the first and second sliders 33a.
・ First and second blank lamps 3 provided on the side of 33b
It is also possible to adopt a configuration in which the position is moved together with 1a and 31b.

A horizontally long spring plate member 38 is attached and supported along the length of the lower surface of the housing 39, and a horizontally long charging roller cleaning pad 4 is attached and held along the length on the lower surface of the spring plate member. There is. The cleaning pad 4 has a length dimension substantially corresponding to the entire length of the charging roller 2, and is normally in a state (non-cleaning state) lifted in a non-contact manner with respect to the charging roller 2 by a spring plate member 38 as a supporting member. Is held.

Convex cam portions 37a and 37b (FIG. 5) are provided on the upper surfaces of the front and rear ends of the spring plate member 38, respectively. In addition, the first and second light irradiation means 30 described above
The outer ends of the sliders 33a and 33b are provided with projecting portions 43a and 43b, which project outward and respectively correspond to the above convex cam portions.

Thus, the first and second sliders 33a.3
3b are respectively held in the home position H on standby, or when the position movements of the 3b are controlled in a direction in which they are spaced from each other in the reduction magnification image forming mode, the first and second fliers 33a and 33b The protruding portion 43a / 4
3b does not interfere with the convex cam portions 37a and 37b on the front side and the rear side of the spring plate member 38, respectively (FIG. 5A).

In this embodiment, a cleaning (cleaning) execution time of the charging roller 2 is set every time the number of formed images reaches, for example, 200 sheets, and a stepping motor 36 of the light irradiating means 30 is set at each time by a control unit (not shown). Control the first
And the second sliders 33a and 33b are moved from their home positions H and H, respectively, in a direction in which the distance between them is further increased, as indicated by the three-dot chain line in FIG.

The first and second sliders 33a and 33b
The movements in the direction of increasing the mutual distance are performed until the actuator 44 provided on the first slider 33a is detected by the position detection means 45 such as a photo sensor provided on the housing 39.

As a result, the first and second sliders 33a
As shown in FIG. 5B, the protrusions 43a, 43b on the side 33b come into contact with the front side and the rear side convex cam portions 37a, 37b of the spring plate member 38, respectively.
b is pushed up against the elasticity of the spring plate member 38. As a result, the spring plate member 38 is lowered and the cleaning pad 4 is brought into contact with the charging roller 2 with a predetermined pressure (cleaning state).

The contact operation of the cleaning pad 4 with the charging roller 2 is performed in a sequence of non-image forming periods such as the pre-multi-rotation period, the pre-rotation period, the paper interval, and the post-rotation period of the image forming process. As the charging roller 2 rotates, the cleaning pad 4 contacting the cleaning roller 4 cleans the entire circumferential surface of the charging roller 2.

After the cleaning of the charging roller 2 by the contacting cleaning pad 4 is performed for a predetermined time (for example, during several rotations of the charging roller 2), the control unit controls the stepping motor 36 to control the first and second sliders. 33a
33b is returned to the home position H · H and operated.

As a result, the first and second sliders 33a
The projecting portions 43a and 43b of 33b are respectively the spring plate members 3
8 is released from the front and rear convex cam portions 37a and 37b to release the pushing up of the spring plate member 38, and the cleaning pad 4 changes from the contact state with the charging roller 2 in FIG. ) Returned to the non-contact state and held.

Then, every time the charging roller cleaning time set in advance in the control section (every 200 sheets of image formation is completed in this example).
As described above, the position movement operation of the light irradiation means 30 to the outside of the first and second sliders 33a and 33b is performed, so that the cleaning pad 4 is brought into contact with the charging roller 2 in conjunction therewith. The cleaning process of the charging roller 2 is intermittently executed.

In this embodiment, as described above, the light irradiating means 30 originally arranged in the image forming apparatus is also used as the contact control means of the cleaning pad 4 with respect to the charging roller 2, as described above. Compared to the case where a dedicated mechanism such as a link mechanism that uses a solenoid is installed in the charging roller, the structure of the charging roller cleaning means is simplified, and the installation space is saved, which allows the device to be downsized and the cost to be reduced. Become. There is no problem of sudden sound when the solenoid is operated unlike the link mechanism using the solenoid.
Further, in this embodiment, the pushing force acts on the cleaning pad 4 at two positions at both ends in the longitudinal direction, so that the pressure of the cleaning pad 4 can be uniformly applied to the charging roller 2 in the longitudinal direction of the charging roller. No bad cleaning will occur.

The cleaning pad 4 is brought into contact with the charging roller 2 intermittently for a predetermined time and for a predetermined time to clean the charging roller 2, and is otherwise kept in a non-contact state, so that the cleaning pad 4 is durable. Be promoted.

<Embodiment 2> (FIG. 6) In this embodiment, the charging roller 2 is moved in the contact direction at the time of cleaning with respect to the cleaning pad 4 fixedly arranged.

That is, as shown in FIG. 6A, the charging roller 2 has one end arm which is vertically swingable about the support shaft 51 and which has one arm on one side of a pair of front and rear levers 52. It is rotatably supported and disposed between the tip ends of the. The pair of levers 52 are each biased clockwise by a tension spring 53 as a biasing member about the support shaft 51, and the charging biasing force causes the charging roller 2 to move in a predetermined direction relative to the photosensitive drum 1. The photosensitive drum 1 is kept in pressure contact with the pressing force of, and is rotated by the rotation of the photosensitive drum 1.

The pair of front and rear levers 51
The inner surface side of 51 is provided with tapered sloped cam portions d and d as shown in FIG. 6B.

Similar to the apparatus of the first embodiment, the first and second sliders 33a and 33b of the light irradiating means 30 are moved from their home positions H and H at each charging roller cleaning time preset in the control section. Is also controlled to be moved outward, so that the first and second sliders 3
The protrusions 43a and 43b of 3a and 33b are inclined cam portions d of the front and rear levers 52 and 52, respectively.
It hits against d and interferes, so that both levers 52.5
2 are supporting shafts 51, against the tension springs 53, 53, respectively.
The charging roller 2 is lifted away from the photosensitive drum 1 by being rotated counterclockwise about 51, and the upper surface side thereof is fixedly arranged to the immovable member such as the lower surface of the housing 39 of the light irradiation means 30. It comes into contact with the cleaning pad 4. When the levers 52, 52 are rotated counterclockwise to bring the charging roller 2 into contact with the cleaning pad 4, the charging roller 2 is connected to the photosensitive drum 1 and the like via a power transmission means (not shown) such as a gear. Is rotated and driven by the drive transmission from the drive source, and the outer peripheral surface is rubbed with the cleaning pad 4 to clean the charging roller 2.

After completion of cleaning for a predetermined time, the first and second sliders 33a and 33b return to the home position H.
By returning to H, the interference of the protrusions 43a and 43b with the sloped cam portions d and d is released, and the lever 5 is released.
2 ・ 52 is a support shaft 51 ・ 51 by a tension spring 53 ・ 53.
When the charging roller 2 is rotated in the clockwise direction about the position, the charging roller 2 is separated from the cleaning pad 4 and returns to the state of being pressed against the photosensitive drum 1 again.

<Embodiment 3> (FIG. 7) In this embodiment, an image forming lens (lens group) 26 as an image forming means for the photosensitive drum 1 is also used as a contact control means for the cleaning pad 4 with respect to the charging roller 2. It is a thing.

The imaging lens 26 is driven in a predetermined range (magnification moving range) D in the optical axis direction by a driving mechanism such as a motor (not shown) controlled by a controller (not shown) according to the magnification (enlargement / reduction) of the formed image. The position movement is controlled at.

The cleaning pad 4 is mounted and supported by a spring plate member 38 as a support member fixedly supported by the immovable member 60, and is normally lifted in a non-contact manner from the charging roller 2 in a state shown by a solid line (non-cleaning). State).

Reference numeral 61 denotes a lever which can freely rotate about a support shaft 62, and is always biased to rotate clockwise by a tension spring 63, and is received by a stopper 64 in a free state to rotate substantially vertically as shown by a solid line. It is held in an angular position. The upper end of the lever 61 is located on the movement locus of the imaging lens 26, and the lower end is located corresponding to the engaging portion 38 a of the spring plate member 38.

The position of the imaging lens 26 is normally controlled in a predetermined magnification movement range D in accordance with the magnification of the formed image.
It does not interfere with the upper end of the lever 61.

As in the first embodiment, the control unit controls the imaging lens driving mechanism unit (not shown) at every predetermined charging roller cleaning time to move the imaging lens 26 beyond the normal magnification moving range D. The lever 61 is moved by a predetermined amount in a direction in which it interferes with the upper end portion of the lever 61 as indicated by a two-dot chain line.

By the movement of the imaging lens 26, the imaging lens 26 (or the movable member for moving the position of the imaging lens) interferes with the upper end portion of the lever 61, and the lever 61 is resisted against the tension spring 63. The support shaft 62 is rotated counterclockwise, and the lower end of the lever 61 causes the engagement portion 3 to rotate.
The spring plate member 38 is pushed downward against the elasticity by the pressing force against 8a, the cleaning pad 4 is brought into a state of being pressed against the upper surface of the charging roller 2 with a predetermined pressing force, and the cleaning of the charging roller 2 is executed. To be done.

After completion of cleaning for a predetermined time, the imaging lens 26 is moved back within the predetermined magnification moving range D to cancel the interference with the upper end of the lever 61, and the lever 61 is again stopped by the tension spring 63. The cleaning pad 4 is rotated clockwise until it is received by 64, and the cleaning pad 4 is returned and held in a state of being lifted from the charging roller 2 in a non-contact manner.

In the image forming apparatus, the light irradiation means 60
Since the load for moving the imaging lens 26 is usually larger than the load for moving the.
The movement driving force of the imaging lens 26 is larger. Therefore, as in the present embodiment, the one in which the image forming means 26 is also used as the contact control means of the cleaning pad 4 with respect to the charging roller 2 is effective when the contact pressure between the cleaning pad 4 and the charging roller 2 is set to be large. is there.

Further, in a device in which the blank lamps 31a and 31b move in correspondence with only the copy magnification regardless of the size of the transfer material, the movement of the blank lamp is interlocked with the movement of the imaging lens 26 using a cam or the like. There is also a configuration in which the blank lamp does not have a drive source independently by performing the operation. In this case, the same effect can be obtained even if the cleaning pad 4 is pushed up by the driving force of the imaging lens 26 via the blank lamp supporting members (slider) 33a and 33b to bring the cleaning pad 4 and the charging roller 2 into contact with each other. Needless to say.

The contact charging member may have a shape other than the roller shape.

[0074]

As described above, according to the present invention, in the image forming apparatus using the contact charging means as the charging processing means of the image carrier, the solenoid is used as the contact controlling means of the cleaning member with respect to the contact charging member. Compared with the case where a dedicated mechanism such as a link mechanism is provided, the mechanism configuration of the contact charging member cleaning means is simplified, and the installation space is not required, and the device can be downsized and the cost can be reduced. There is no problem of the sudden sound at the time of operation unlike the link mechanism using the solenoid. Further, with a simple mechanism configuration, it is possible to bring the cleaning member and the contact charging member into contact with each other at a predetermined pressure evenly along the length by the means configuration that does not take up an installation space. It is possible to secure and maintain a good cleaning state of the contact charging member without causing cleaning failure due to uneven contact pressure.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus as an example.

FIG. 2 is a perspective view of a light irradiation unit (blank exposure unit).

FIG. 3 is an explanatory diagram of operation and irradiation range (blank dew wide area)

FIG. 4 is an explanatory diagram of a luminous flux and an optical path of a blank lamp.

5A and 5B are explanatory views of a protrusion and a convex cam that bring a cleaning pad into and out of contact with a charging roller. FIG. 5A is a non-cleaning state, and FIG. 5B is a cleaning state.

FIG. 6 (A) is a main part view of the device according to the second embodiment, and FIG. 6 (B) is a view of a slope cam part provided on a lever.

FIG. 7 is a main part diagram of an apparatus according to a third embodiment.

[Explanation of symbols]

 1 Image Carrier (Photosensitive Drum) 2 Contact Charging Member (Charging Roller) 4 Cleaning Member (Cleaning Pad) 29 Image Forming Means (Image Forming Lens) 30 Light Irradiating Means (Blank Exposure Means) 31a / 31b Light Emitting Body (Blank Lamp) 32a / 32b Light flux regulating member (reflector)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G03G 15/04 114 9122-2H 21/10

Claims (3)

[Claims] 1. An image forming apparatus using a contact charging means as a charging processing means for an image bearing member, comprising a cleaning member for the contact charging member contacting the image bearing member,
The movable image forming process means whose position movement is controlled according to the image forming condition is controlled to move for a predetermined time for each contact charging member cleaning time calculated by the control system, and is interlocked with the movement of the means. The cleaning member and the contact charging member are relatively moved from the non-contact state to the contact direction to bring them into contact with each other, thereby cleaning the contact charging member for the predetermined time. Forming equipment. 2. The movable image forming process means comprises:
One or both of a light emitting body and a light flux regulating member of the light emitting body, which removes electric charges charged in an image carrying body portion other than a recorded image area in an electrostatic charge image formed on the image carrying body, form a magnification of a formed image. The position of the light irradiating means is controlled according to the above, and the light irradiating means is moved to a predetermined position for a predetermined time at each cleaning time of the contact charging member calculated by the control system. 2. The cleaning of the contact charging member is carried out for the predetermined time by interlockingly moving the cleaning member and the contact charging member in a contact direction from a non-contact state to bring them into contact with each other. The image forming apparatus according to item 1. 3. The movable image forming process means comprises:
Positioning control is performed for the image light on the image carrier, the position of which is controlled according to the magnification of the formed image, and the imaging means is provided at a predetermined time for each contact charging member cleaning time calculated by the control system.
The contact charging member is cleaned for the predetermined time by moving the cleaning member and the contact charging member relative to each other in the contact direction by moving the cleaning member and the contact charging member in a contact direction in association with the movement of the means. The image forming apparatus according to claim 1, wherein the image forming apparatus is executed.