JPH06230709A - Electrostatic recorder and its cleaning device - Google Patents

Abstract

PURPOSE:To maintain cleaning performance stable over a long period. CONSTITUTION:The cleaning device of the electrostatic recorder which is provided by bringing the toner end side into contact with the latent image forming surface of an image carrying member 1 having the latent image forming surface and moving in a developing position holding the latent image and removes the residual toner on the image carrying member 1 used for development of the latent image by scraping away the toner, is constituted of a cleaning blade 81 which is formed out of a metallic plate material, is flattened on at least the contact part side facing the latent image forming surface of the image carrying member 1 and is arranged with the contact part side inclining so as to follow the moving direction of the image carrying member 1, and pressurizing means 87, 87 which pressurize the cleaning blade 81 evenly toward the image carrying member 1 near the contact point with the image carrying member 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic recording device such as an electrophotographic copying machine which forms a latent image, develops it with toner, and transfers it to a recording sheet to perform recording. In particular, the present invention relates to improvement of a cleaning device for holding a toner image and removing residual toner on the electrostatic image bearing member.

[0002]

2. Description of the Related Art An electrophotographic image forming apparatus (recording apparatus) is widely used as a copying machine, a printer or the like. Here, FIG. 6 shows a configuration example of a dry electrostatic recording apparatus which is an electrophotographic recording apparatus. The configuration example shown in FIG. 6 is an example of an electrostatic recording device called ionography, and is a diagram for explaining an outline thereof.

In the figure, reference numeral 1 is an image carrier, which uses a dielectric drum or the like. 2 is a latent image forming device,
A latent image forming apparatus such as an ion cartridge that forms an electrostatic latent image on the image carrier 1. A developing device 3 develops the electrostatic latent image formed on the image carrier 1 by the latent image forming device 2 as a toner image.

The developing device 3 is a housing 3 containing a toner 3b.
A roller 3c is arranged in a, and the toner 3b is attached to the surface of the roller 3c to convey the toner to the image carrier 1. The roller 3c is arranged so as to be in contact with the surface of the image carrier 1, and rotates at the same peripheral speed as the image carrier 1 to adhere the toner 3b. Reference numeral 3d is a film thickness adjusting blade for making the toner 3b adhering to the surface of the roller 3c uniform in thickness.

Reference numeral 4 denotes a transfer device for transferring the toner image on the image carrier 1 onto the recording paper 5.
By generating corona ions of positive polarity or negative polarity and radiating the corona ions toward the image carrier 1 through the recording paper 5, the toner image on the image carrier 1 is charged on the charged recording paper 5. It is adsorbed and transferred.

That is, the transfer device 4 is opposed to the image carrier 1 via the conveying path of the recording paper, and the image carrier 1
The recording paper 5 is electrified by irradiating the back surface of the recording paper 5 conveyed in contact with the recording paper 5 and the toner image on the image carrier 1 is electrostatically attracted to the recording paper 5 by the electrostatic attraction force. Transfer to.

Reference numeral 6 denotes a paper conveying device for conveying the recording paper 5 having the unfixed toner image transferred by the transfer device 4. 7 is a fixing device,
This is for fixing the unfixed toner image on the recording paper 5 which is conveyed by the paper conveying device 6.

Reference numeral 8 denotes a cleaning device for scraping off the remaining toner image on the image carrier 1 which is left without being transferred to the recording paper 5. The cleaning system is a stainless steel or urethane blade cleaning. And fur brush cleaning are often used. An eraser 9 is for erasing the electrostatic latent image formed on the image carrier 1. An AC corona charge eliminator is used as the eraser 9.

Reference numeral 10 denotes a paper feeding device, which is a recording paper cassette 10a in which cut papers (standard recording papers) are stacked and stored.
And a feeding roller 10b for feeding the recording papers 5 one by one from the recording paper cassette 10a, and feeds the recording papers 5 one by one toward a transfer section constituted by the image carrier 1 and the transfer device 4. It is for sending.

Reference numeral 11 denotes a paper feed unit paper guide, which guides the recording paper 5 fed by the paper feed device 10 to the transfer unit. Further, 13 is a collecting device, which is a collecting device for collecting the toner scraped off by the cleaning device 8, and 14 is a guide, which fixes the recording paper 5 on which the unfixed toner image is transferred. It is for leading to the device 7.

The image carrier 1 has a drum shape, and a latent image forming device 2, a developing device 3, a transfer device 4, a toner collecting device 13, a cleaning device 8 and an eraser 9 are arranged at fixed positions around the drum. As the image carrier 1 rotates, the peripheral side surface sequentially passes through these positions.

The paper carrying device 6 fixes the recording paper 5 to which the toner image is transferred and sent out through the transfer device 4 and the fixing device 7.
And a suction fan 16 for sucking and holding the pair of belts, and a suction fan 16 for holding the belts by the belt conveyance mechanism. By suctioning the recording paper 5 downward by the provided suction fan 16 and holding the recording paper 5 in the belt conveyance mechanism, the recording paper 5 is conveyed in the forward direction by the belt conveyance mechanism, whereby the recording paper 5 having the unfixed toner image. The unfixed toner image holding surface does not disturb the image by coming into contact with the lower portion of the toner collecting device 13 or the like.

Paper is fed between the exit of the transport path of the paper transport device 6 and the entrance of the transfer portion, between the exit of the paper separation mechanism of the paper feeding device 10 and the entrance of the transfer portion, and between the option feeder and the entrance of the transfer portion. A paper guide 11 is provided.

The fixing device 7 applies heat to the recording paper 5 having an unfixed toner image to melt the toner on the recording paper 5 and bring it into close contact with the recording paper 5, and together with the heat roll 17, recording is performed. The recording paper 5 is composed of a pressure roller 15 that picks up the paper 5 and conveys the paper 5 while applying pressure.
The toner image is fixed by being conveyed while being pressed against the heat roll 17 by the pressure roller 15.

The recording apparatus having such a structure is used as the sheet feeding device 1.
An unfixed toner image is formed on one side of the recording sheet (recording sheet) 5 fed out by 0 and conveyed to the image forming section at the transfer section, and the toner image is fixed by the fixing device 7.

That is, the image carrier 1 is used for recording.
While rotating at a constant speed in the direction of arrow R, the latent image forming device 2 forms an electrostatic latent image of an image on the peripheral surface thereof, and the developing device 3 applies toner to the electrostatic latent image on the image carrier 1. A toner image is formed by attaching toner to the latent image. A transfer device 4 for generating corona ions is arranged to face the image carrier via the transport path of the recording paper, and is in contact with the image carrier 1 and transported at the same speed as the image carrier 1. From the back surface of the recording paper 5, the transfer device 4 applies corona ions to charge the recording paper 5, and the electrostatic attraction force due to the charging transfers the toner image on the image carrier 1 onto the recording paper 5. Let Then, the recording paper 5 on which the toner image is transferred is sent to the fixing device 7 by the conveying device 6 and is thermally fixed.

In this way, the latent image is developed with the toner as the developer, transferred to the recording paper and thermally fixed, thereby printing. The transfer residual toner on the image carrier 1 after the transfer is removed by the cleaning device 8. In addition to such an ionography printer (IDP), there is a laser beam printer (LBP) that forms a latent image on the image carrier 1 with a laser beam.

In the case of LBP, the structure is as shown in FIG.
A photosensitive drum 51 is used as the image carrier. Then, while the photoconductor drum 51 is rotated in the direction of arrow R at a constant speed, a uniform charge is formed on the photoconductor drum 51 by the charger 59, and a laser is generated by a laser optical system 52 which is a latent image forming device. A latent image is formed by scanning the beam. Further, in the case of LBP, an optical static eliminator 57 for erasing light by applying light is used as an eraser. Despite these differences, the basic principle of the dry electrophotographic recording apparatus is basically the same regardless of whether it is LBP or ionography.

In FIG. 7, 52a is a laser light source, 52b is a polygon mirror, 53 is a developing device, 54 is a transfer device, 55 is a fixing device, 56 is a cleaning device, and
Reference numeral 58 is a paper feeding device.

By the way, in the dry type electrophotographic recording apparatus, after the electrostatic latent image is formed on the photosensitive member or other drum-shaped image carrier as described above, the image is developed by the developing apparatus and recorded. An image is formed on the transfer material by transferring it to a transfer material such as paper. At that time, there is toner remaining on the image carrier without being transferred to the transfer material. The use of the cleaning device is as described above.

As the cleaning blade, conventionally, a material such as a rubber blade which has elasticity and does not damage the surface of the image bearing member has been widely used, but a cleaning blade made of such a material causes abrasion. Big again
The cleaning blade is used by directly contacting the surface of the image carrier, and since the cleaning blade is arranged so as to project obliquely in the direction opposite to the rotation direction of the image carrier, long-term contact may prevent fatigue. It is easy to occur.

When such deterioration occurs, the cleaning action is impaired, and the image quality of the output print deteriorates. Therefore, in order to maintain the image quality, the blade of the cleaning device must be frequently replaced,
Maintenance is difficult and costly.

Therefore, as a cleaning device improved in this respect, a cleaning device as shown in FIG. 8 has been proposed. This is the structure disclosed in JP-A-55-89883, and uses a belt-shaped cleaning blade made of a thin piece of metal as a material. That is, the cleaning blade 8a made of a thin piece of metal as shown in FIG. 8 is pressed against the surface of the image carrier 1 to scrape off the residual toner.

In this structure, as shown in the drawing, the length of the cleaning blade 8a made of a thin metal piece is set so as to be in a counter state in the rotation direction of the photosensitive drum (image carrier) 1 (direction of arrow R). One side edge of the side is arranged in contact. That is, the blade edge (in this case, the one side edge on the longitudinal side of the thin metal blade 8a) is projected in such a manner that it faces the rotational direction of the photosensitive drum 1, and the blade edge (the one side described above) is formed on the surface of the photosensitive drum 1. The edges).

In the case of this cleaning device, the thickness of the cleaning blade 8a is 0.01 mm to 0.3 mm, and the length of the tip of the cleaning blade (backward) is 1 m.
m to 15 mm, the contact angle of the blade 8a with respect to the surface of the photosensitive drum 1 (the angle at which the cutting edge is applied) is in the range of 2 to 45 degrees, and the contact pressure of the cleaning blade 8a on the surface of the photosensitive drum 1 is 10 g. It is set in the range of up to 2000 g.

By using such a cleaning device, the cleaning blade is less worn than the rubber blade, and even if the cleaning blade is kept in contact with the image carrier for a long period of time, no fatigue occurs.
A good cleaning action can be maintained for a long period of time.

[0027]

As described above, as the blade of the cleaning device, a rubber blade or the like, which may be worn when using a material which is elastic and does not damage the surface of the image carrier, In order to eliminate the drawback that it is liable to cause abrasion, by using a blade made of a thin metal piece, wear of the cleaning blade is small even when used for a long period of time as compared with a rubber cleaning blade, and the cleaning blade is also used. Even if the image bearing member is kept in contact with the image bearing member for a long period of time, the advantage that no settling occurs is obtained. However, on the other hand, the following problems arise.

Generally, when an attempt is made to remove the residual toner on the image bearing member with the cleaning blade, in order to perform good cleaning, the edge (tip edge) of the cleaning blade is surely covered over the entire width of the image bearing member. It is necessary to make contact with. This is an indispensable condition for exhibiting good cleaning performance.

Considering that the wear is small, if the cleaning blade is arranged so as to be at right angles to the surface of the image carrier, the frictional resistance will be small, and it will be oblique to the image carrier. Since it does not scoop up, it also protects the surface of the image carrier.

However, since the cleaning blade made of a thin metal piece is less elastically deformed at the contact point with the image carrier, it is necessary to mount the cleaning blade at such a right angle to the surface of the image carrier. Inaccurate accuracy leads to deterioration of cleaning performance.

That is, due to the delicate displacement of the cleaning blade by the metal flakes, a gap is likely to be formed between the edge of the cleaning blade and the image carrier, and when such a gap is formed, the cleaning blade is the metal flakes. Therefore, unlike the case of rubber, it cannot be absorbed by the elastic deformation of the edge of the cleaning blade, so that the gap remains.

Therefore, in the case where the cleaning blade is slightly displaced due to vibration or fluctuation of the friction coefficient of the cleaning blade with respect to the image carrier at the time of activation of the image carrier, the edge of the cleaning blade and the image A gap is formed between the carrier and the toner, and the toner is apt to be caught in the carrier, and cleaning failure is likely to occur.

In order to prevent such a defect, in the conventional system shown in FIG. 8, the cleaning blade 8a is attached to the image carrier 1.
On the other hand, the components are brought into contact with each other in the counter direction and the component force of the frictional force of the edge is used as the pressure contact force. This is because the surface of the image carrier 1 is scooped by the edge of the cleaning blade 8a, which is not desirable from the viewpoint of protecting the surface of the image carrier 1, but by examining the materials, the thickness and surface of the cleaning blade 8a It can be dealt with by devising the polishing state of.

However, in such a configuration, as shown in FIG.
As shown in FIG. 9, when the edge of the cleaning blade 8a is worn, the edge of the cleaning blade 8a becomes sharp and the edge is easily deformed.
As shown in (b), when the edge is turned up, defective cleaning occurs from that portion. That is, FIG. 9 (c)
As shown in FIG. 5, the residual toner 3a on the surface of the image carrier 1 withstands the edge portion of the cleaning blade 8a, which further generates a force F for lifting the edge, further increasing the deformation and preventing the toner from being removed. I will end up.

Therefore, an object of the present invention is to maintain electrostatic cleaning in a stable manner for a long period without lowering the cleaning performance even if the edge of the cleaning blade is worn. An object of the present invention is to provide an apparatus and its cleaning apparatus.

[0036]

In order to achieve the above object, the present invention has the following constitution. That is, firstly, one end side of the latent image forming surface of the image carrier that holds the latent image and moves the developing position while holding the latent image is provided so as to contact the latent image forming surface. In a cleaning device of an electrostatic recording device, which removes the residual toner on the image bearing member, which has been subjected to development, by scraping it, the toner is formed of a metal plate material,
A cleaning blade in which at least the contact portion side with respect to the latent image forming surface of the image bearing member is flattened, and the contact portion side is inclined to follow the moving direction of the image bearing member,
The cleaning blade is composed of a pressing unit that uniformly presses the cleaning blade toward the image carrier near the contact point with the image carrier.

Secondly, a latent image forming means, a developing means, a transfer means, and a cleaning means are formed in order around the image carrier which has a drum shape and which has a latent image forming surface on the surface and is rotationally driven. The latent image formed by the latent image forming unit is converted into a toner image by the developing unit at the developing position, transferred to the recording sheet by the transfer unit at the transfer position, and the residual toner is removed by the cleaning unit at the cleaning position. In the electrostatic recording device designed to be removed, the image carrier is made of a resin that holds a latent image, and a pigment is added to the resin, and the cleaning means is a metal plate-shaped cleaning blade. And the front end of the cleaning blade is formed flat, and the front end of the cleaning image is formed on the latent image forming surface of the rotating image carrier. The tip of the cleaning blade is disposed so as to be inclined according to the moving direction of the holding body, the tip portion is in contact with the latent image forming surface of the image bearing body, and the cleaning blade is uniformly applied to the image bearing body near the contact point with the image bearing body. The pressure is applied by the pressure applying means.

[0038]

In such a structure, in the case of the first structure,
A cleaning device of the electrostatic recording device is composed of a cleaning blade made of a metal plate and a pressing means for pressing the cleaning blade to the image carrier side, and the cleaning blade is at least a contact portion with respect to the latent image forming surface of the image carrier. The side is made flat and the contact side is inclined so as to follow the moving direction of the image carrier. That is, the cleaning blade is arranged so as to be inclined so that the contact portion is slid in the moving direction of the image carrier. The cleaning blade has a flat contact portion side with respect to the latent image forming surface of the image bearing member, and is pressed toward the image bearing member side from the back side in the vicinity of the contact point with the image bearing member. The blade is in close contact with the peripheral surface of the image carrier with a uniform pressure, and since the contact with the image carrier is in a state not against the rotation of the image carrier, the contact end portion does not deform, and the material Since it is also a metal, it has little wear, and since the cleaning blade is constantly pressed against the peripheral surface of the image carrier with a uniform pressure, the adhesion to the image carrier can be maintained for a long time even if there is wear. Therefore,
The residual toner can be removed in a good state for a long period of time, and the cleaning effect can be maintained.

In the case of the second structure, the latent image forming means, the developing means, the transfer means and the cleaning means are arranged in this order around the drum-shaped image carrier which is rotationally driven, and the latent image forming means is formed. The latent image is converted to a toner image by the developing device at the developing position, transferred to the recording sheet by the transferring device at the transferring position, and the residual toner is removed by the cleaning device at the cleaning position. In the apparatus, the image carrier is made of a resin that holds a latent image, and a pigment is added to the resin to increase the strength. And the first
By using the cleaning means such as
An electrostatic recording device that can prevent damage to the image carrier due to contact with the cleaning blade, has high durability in combination with the effect of the first configuration, and can maintain the cleaning effect for a long period of time. Can be provided.

[0040]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a schematic configuration diagram of a main part showing an example of an electrostatic recording apparatus (image forming apparatus) adopting a cleaning device according to the present invention. Also, FIG.
FIG. 2A is a perspective view of a cleaning device according to the present invention, and FIG. 2B is a sectional view thereof.

The configuration example shown in FIG. 1 is an example of an electrostatic recording apparatus called ionography, and its outline will be described.
In the figure, reference numeral 1 denotes an image carrier, which uses a dielectric drum or the like. Reference numeral 2 denotes a latent image forming device, which is an image carrier 1
It is a latent image forming device such as an ion cartridge that forms an electrostatic latent image on the. A developing device 3 develops the electrostatic latent image formed on the image carrier 1 by the latent image forming device 2 as a toner image.

The developing device 3 includes a housing 3 containing a toner 3b.
A roller 3c is arranged in a, and the toner 3b is attached to the surface of the roller 3c to convey the toner to the image carrier 1. The roller 3c is arranged so as to be in contact with the surface of the image carrier 1, and rotates at the same peripheral speed as the image carrier 1 to adhere the toner 3b. Reference numeral 3d is a film thickness adjusting blade that makes the toner 3b adhering to the surface of the roller 3c have a uniform thickness.

Reference numeral 4 denotes a transfer device for transferring the toner image on the image carrier 1 onto the recording paper 5.
By generating corona ions of positive polarity or negative polarity and radiating the corona ions toward the image carrier 1 through the recording paper 5, the toner image on the image carrier 1 is charged on the charged recording paper 5. It is adsorbed and transferred.

That is, the transfer device 4 is opposed to the image carrier 1 via the conveyance path of the recording paper, and the image carrier 1
The recording paper 5 is electrified by irradiating the back surface of the recording paper 5 conveyed in contact with the recording paper 5 and the toner image on the image carrier 1 is electrostatically attracted to the recording paper 5 by the electrostatic attraction force. Transfer to.

Reference numeral 6 denotes a paper conveying device for conveying the recording paper 5 having the unfixed toner image transferred by the transfer device 4. 7 is a fixing device,
This is for fixing the unfixed toner image on the recording paper 5 which is conveyed by the paper conveying device 6.

Reference numeral 80 denotes a cleaning device according to the present invention, which is an image carrier 1 which is not transferred to the recording paper 5 and remains.
This is for scraping off the rest of the upper toner image, and the details thereof will be described later, but the cleaning method is a method of scraping it using a cleaning blade 81 made of a metal thin piece (metal thin plate).

In the present invention, the cleaning device 80
Is a configuration in which the tip side edge of the cleaning blade 81 is inclined and brought into contact with the downstream side in the rotation direction of the image carrier 1.
This is a configuration in which the surface of the image carrier 1 is scraped in such a manner that it can be dragged.

That is, in the conventional method, the cleaning blade is arranged in contact with the surface of the image carrier 1 so as to stand in the direction of rotation of the image carrier 1 (in the form of being scraped by the cutting edge). It is arranged in contact with the surface of the image carrier 1 in a shape (not opposed to the rotation direction). An eraser 9 is for erasing the electrostatic latent image formed on the image carrier 1. An AC corona charge eliminator is used as the eraser 9.

Reference numeral 10 denotes a paper feeding device, which is a recording paper cassette 10a in which cut papers (standard recording papers) are stacked and stored.
And a feeding roller 10b for feeding the recording papers 5 one by one from the recording paper cassette 10a, and feeds the recording papers 5 one by one toward a transfer section constituted by the image carrier 1 and the transfer device 4. It is for sending.

Reference numeral 11 denotes a paper feed unit paper guide, which guides the recording paper 5 fed by the paper feed device 10 to the transfer unit. Further, 13 is a collecting device, which is a collecting device for collecting the toner scraped off by the cleaning device 8, and 14 is a guide, which fixes the recording paper 5 on which the unfixed toner image is transferred. It is for leading to the device 7.

The image carrier 1 is drum-shaped, and a latent image forming device 2, a developing device 3, a transfer device 4, a toner collecting device 13, a cleaning device 8 and an eraser 9 are arranged at fixed positions around the drum. As the image carrier 1 rotates, the peripheral side surface sequentially passes through these positions.

The paper carrying device 6 fixes the recording paper 5 to which the toner image has been transferred and sent out through the transfer device 4 and the fixing device 7.
And a suction fan 16 for sucking and holding the pair of belts, and a suction fan 16 for holding the belts by the belt conveyance mechanism. By suctioning the recording paper 5 downward by the provided suction fan 16 and holding the recording paper 5 in the belt conveyance mechanism, the recording paper 5 is conveyed in the forward direction by the belt conveyance mechanism, whereby the recording paper 5 having the unfixed toner image. The unfixed toner image holding surface does not disturb the image by coming into contact with the lower portion of the toner collecting device 13 or the like.

Between the exit of the transport path of the paper transport device 6 and the entrance of the transfer part (the entrance of the transfer device 4), between the exit of the paper separation mechanism of the paper feeding device 10 and the entrance of the transfer part, and from the option feeder to the transfer part entrance. Paper feed section paper guides 11 are provided between the sheets.

The fixing device 7 applies heat to the recording paper 5 having an unfixed toner image to melt the toner on the recording paper 5 and bring it into close contact with the recording paper 5, and together with the heat roll 17, recording is performed. The recording paper 5 is composed of a pressure roller 15 that picks up the paper 5 and conveys the paper 5 while applying pressure.
The toner image is fixed by being conveyed while being pressed against the heat roll 17 by the pressure roller 15. Details of the cleaning device 80 will be described with reference to FIG.

In FIG. 2, the drum-shaped image carrier 1 is rotatably supported by a frame (not shown). When the image carrier drum rotates in the direction of arrow R, a well-known image forming process is performed. , A toner image is formed on the image carrier 1,
It is transferred to a transfer material (not shown). At that time, the toner remaining on the image carrier 1 without being transferred to the transfer material due to the movement of the image carrier 1 is sent to the cleaning device 80 and cleaned.

Cleaning device 8 for performing this cleaning
As shown in FIG. 2, 0 has a belt-like cleaning blade 81 whose free end side edge is in contact with the entire length of the image carrier 1 in the width direction, and this cleaning blade 81 is for holding the blade. It is held by a cleaning blade holder that is a holding mechanism.

The cleaning blade holder comprises a long holding frame 85 having a U-shaped cross section, a blade base 86, and a metal round bar 84. The blade base 86 and the metal round bar 84.
Is held between and. The blade base 86 is a rod-shaped hard member having a rectangular cross section. The holding frame 85 is also a hard member.

That is, in the U-shaped groove of the holding frame 85, a blade base 86 having a length substantially the same as the length of the holding frame 85 is fixed by being moved to one side wall in the groove, and a strip-shaped long strip made of a metal thin piece is fixed. The cleaning blade 81 of the blade base 8
6 is placed in the U-shaped groove of the holding frame 85, and the metal round bar 84 is further pushed into the U-shaped groove of the holding frame 85 to fit the blade base 86 and the packing base. The cleaning blade 81 is held between the elastic member 84 and the elastic member 84. The blade base 86 has a rotation center 86 at both ends thereof.
a, 86b, and the rotation center 86
It is rotatably supported by utilizing a and 86b.

Reference numeral 83 is a contact mechanism for bringing the edge of the cleaning blade 81 into uniform contact with the surface of the image carrier 1, and is a long support frame 83a made of a mold material having a V-shaped cross section.
Install a cantilevered leaf spring 87 inside,
An elongate rod-shaped pressing member 88 made of an elastic material is fixedly provided on the free end side along the longitudinal direction of the leaf spring 87.

Then, the contact mechanism 83 is arranged so that the holding frame 85 holding the cleaning blade 81 is wrapped inside.
The supporting frame 83a constituting the above is arranged, and the edge side of the cleaning blade 81 is brought into contact with the surface of the image carrier 1 by the pressing force of the plate spring 87 via the pressing member 88.

The blade base 86 holding the cleaning blade 81 has rotation centers 86a and 86b at both ends thereof.
By holding it and rotatably supporting it,
The cleaning blade holder is rotatable. The cleaning blade 81 has a strip shape, and the leaf spring 8
7 is also in the form of a strip, and the pressing member 88 intervenes on the free end side of both, so that the biasing force of the leaf spring 87 is applied to the pressing member 88.
Therefore, the cleaning blade 81 can be uniformly transmitted to the cleaning blade 81 via the blade, and the edge of the cleaning blade 81 can be brought into contact with the surface of the image carrier 1 with a uniform pressing force distribution.

Cleaning blade 8 used in the present invention
1 is steel, stainless steel, brass,
Phosphor bronze, beryllium copper, ceramics or the like is used, and as the image carrier 1, a resin in which a pigment is uniformly dispersed in a resin having a function required for latent image formation is used. The reason why the pigment is uniformly dispersed in the image carrier 1 is to reinforce the resin forming the image carrier 1 with the pigment, and the image on the contact surface between the cleaning blade 81 and the image carrier 1 is formed. This is to reduce the amount of deformation of the carrier 1.

In this case, the thickness of the cleaning blade 81 is 0.05 mm to 3 mm, and the amount of protrusion of the blade from the blade holding portion, that is, the cleaning blade 8
The edge side protrusion amount of the cleaning blade 81 from the holding frame 85 holding 1 is 5 mm to 8 mm, and the straightness in the y direction, that is, the edge side longitudinal direction of the cleaning blade 81 is from the minimum particle size of the toner used. Judgment is made so that the cleaning blade 81, which does not pass through this, is set to 50 microns or less, and is brought into contact with the image carrier 1 within a contact angle range of 15 to 70 degrees with the image carrier 1. The contact pressure per unit length (per 1 mm) is about 0.5 g to 10 g so that the image carrier 1 is brought into contact with the contact pressure.

The recording apparatus having such a structure is used as the paper feeding device 1.
An unfixed toner image is formed on one side of the recording sheet (recording sheet) 5 fed out by 0 and conveyed to the image forming section at the transfer section, and the toner image is fixed by the fixing device 7.

That is, in recording, the latent image forming device 2 forms an electrostatic latent image of an image on the peripheral surface of the image bearing member 1 while rotating the image bearing member 1 at a constant speed in the direction of the arrow R, and the developing device 3 causes the toner to grow. Is applied to attach the toner to the electrostatic latent image on the image carrier 1 to form a toner image. A transfer device 4 for generating corona ions is arranged to face the image carrier via a recording paper transport path and is brought into contact with the image carrier 1 at the same speed as the image carrier 1. From the back surface of the recording paper 5, the transfer device 4 applies corona ions to charge the recording paper 5, and the electrostatic attraction force due to the charging transfers the toner image on the image carrier 1 onto the recording paper 5. Let Then, the recording paper 5 on which the toner image is transferred is sent to the fixing device 7 by the conveying device 6 and is thermally fixed.

In this way, printing is performed by developing the latent image with the toner as the developer, transferring the latent image to the recording paper and thermally fixing it. The transfer residual toner on the image carrier 1 after the transfer is removed by the cleaning device 80 in a form of being scraped off by the cleaning blade 81.

As described above, the cleaning blade 81 has its free end side edge in contact with the surface of the image bearing member 1. However, the form is such that the edge is slid on the surface of the image bearing member 1. It is in a state where the surface is inclined. Then, in such a state, the contact mechanism 83 is brought into contact with the surface of the image carrier 1 with a predetermined contact pressure.
It is made to contact by pressure.

The contact mechanism 83 has a leaf spring 87, one end of which is cantilevered and fixed to a support frame 83a forming a part of the frame of the cleaning device 80, and is attached to the free end side of the leaf spring 87. Made of a round bar-shaped pressing material 88,
The spring force generated by the leaf spring 87 is applied to the free end side edge of the cleaning blade 81 via the pressing member 88, and the free end side edge of the cleaning blade 81 is spread over the entire edge and is evenly distributed on the surface of the image carrier 1. Contact.

Since this cleaning blade 81 is made of metal and its mechanical properties are largely different from those of a widely used rubber blade in the related art, the contact surface between the image carrier 1 and the free end side edge of the cleaning blade 81 is large. However, since elastic deformation of the edge can hardly be expected, even if the parameters such as the plate thickness applied to the conventional rubber blade are directly applied, sufficient cleaning performance cannot be obtained.

In this embodiment, the cleaning blade 81
Steel, stainless steel, brass, phosphor bronze, beryllium copper, ceramics, etc. were used as the material for the image carrier 1, and the pigment was uniformly dispersed in the resin having the function required for latent image formation of the main body as the image carrier 1. I tried to use one.

In the case of such a structure of this embodiment, as a result of experiments, the thickness of the cleaning blade is 0.05 mm to 3 mm.
mm, the amount of protrusion of the blade from the blade holding portion is 5 mm to 8 mm, and the straightness in the y direction is 50 mm.
The above-mentioned cleaning blade 81 set to have a micron or less is used, and the contact angle with respect to the image carrier 1 is 15 degrees.
The free end of the cleaning blade 81 is brought into contact with the image carrier 1 within a range of 70 degrees, and with the contact pressure per unit length (per 1 mm) of about 0.5 g to 10 g to contact the surface of the image carrier 1. It was revealed that the side edge is in contact with the surface of the image carrier 1 over the entire area without any gap, and the cleaning performance can be stably maintained for a long period of time without damaging the image carrier 1.

The condition that influences the toner removal ability of the cleaning blade is that the free end side edge of the cleaning blade 81 always contacts the surface of the image carrier 1 over the entire area without any gap, and It is required not to scratch the surface of 1.

In the present embodiment, in order to satisfy these conditions and requirements, the cleaning blade 81 has a straightness defect (out of the straightness condition of 50 μm or less) before the mounting. Even if there is
At the stage of being installed, the cleaning blade 81 can be brought into contact with the image carrier 1 without any gap, and the straightness condition can be satisfied. Moreover, the condition is that the cleaning blade 81 does not bite into the image carrier 1,

Then, as the image bearing member 1, the pigment is uniformly dispersed in the resin having the function required for the latent image formation as described above, and the resin is reinforced by the pigment to form the cleaning blade 81. With the configuration in which the deformation amount of the image carrier 1 on the contact surface of the image carrier 1 is reduced,
The contact pressure of the cleaning blade 81 with respect to the image carrier 1 can be increased so that the edge straightness of the cleaning blade 81 before being incorporated in the recording apparatus does not matter even if it is rough. be able to.

Therefore, the accuracy at the stage of the cleaning blade unit constructed by attaching the cleaning blade to the cleaning blade holder does not have to be very high in terms of straightness, and the assembling accuracy and finishing accuracy are not required. In terms of, you can have a considerable margin.

Therefore, the structure for holding the cleaning blade 81 on the cleaning blade holder can be simply structured as shown in FIG. 3 in this embodiment.

That is, the cleaning blade unit is composed of a blade base 86, a metal round bar 84, and a holding frame 85, and the rod-shaped blade base 86 is fixed to one side wall in the groove of the holding frame 85 having a U-shaped cross section. The wall surface of the blade base 86 in the groove of the holding frame 85 is attached to the cleaning blade 81.
The cleaning blade 81 is applied so as to serve as the supporting surface, and the metal round bar 84 is pushed in from the direction of the arrow C so as to fill the gap X in the groove of the holding frame 85 to assemble.

As a result, the cleaning blade 81
Can be fixed in the groove in the holding frame 85 by being held between the blade base 86 and the metal round bar 84,
Easy to assemble.

With this fixing method, when the cleaning blade 81 having the above-mentioned material and thickness is used, the metal cleaning blade 8 of the blade base 86 is used.
If the flatness of the contact surface with 1 is 0.03 mm or less, the straightness of the edge of the cleaning blade 81 can be surely set to 50 μm or less without paying much attention, and the toner can be removed. Never miss it.

The contact mechanism of the cleaning blade is shown in FIG.
As described above, the image bearing member 1 of the cleaning blade 81 includes the leaf spring 87 and the pressing member 88, and the pressing member 88 made of an elastic member fixed near the free end of the plate spring 87 having one end fixed thereto. The contact pressure is applied to the blade edge by pressing in the vicinity of the contact point.

The contact pressure is 0.
5g-10g is suitable. This contact pressure is applied to the vicinity of the contact point between the cleaning blade 81 and the image bearing member 1 as described above. However, since the pressing point is near the contact point of the image bearing member 1, the cleaning blade passes through the pressing member 88. By applying a pressing force to 81, the contact pressure obtained by the pressing force is prevented from affecting the straightness of the edge of the cleaning blade 81 that contacts the image carrier 1.

According to the experiment, the hardness of the pressing member 88 is
A value of 40 degrees to 80 degrees is suitable, and by selecting a value in this range, it is possible to prevent the adverse effect on the edge straightness when the cleaning blade 81 is brought into pressure contact with the image carrier 1 and to vibrate the edge. It turned out that can also be prevented.

As described above, in the cleaning device 80 of the first embodiment, the cleaning blade 81 is tilted so that its edge is directed in the rotation direction of the image carrier, and brought into contact with the surface of the image carrier. As the cleaning blade 81, a thin metal piece is used. The cleaning blade 81 is held by a cleaning blade holder (holding mechanism), and the cleaning blade 81 is pressed from the back side by a contact mechanism provided separately to carry an image. The image carrier 1 is configured to be brought into uniform contact with the surface of the body 1, and a pigment is added to the material of the image carrier 1 to maintain the strength. As a result, the pressing force of the contact mechanism is applied to the entire edge of the cleaning blade 81, and Cleaning blade on the surface of the image carrier 1 with a straightness of 50 μm or less without damaging the image carrier 1. It is possible to contact, since the minimum particle diameter of the toner typically used less than 50 microns, it is possible to capture without missing a toner having such a particle size.

In addition, since the edge of the cleaning blade is directed in the forward direction with respect to the rotation direction of the image carrier 1 and does not oppose it, there is no fear of warping or cracking of the edge tip, and there is no concern for a long time. Therefore, the cleaning performance can be maintained.

Further, since the cleaning blade is made of metal as a material, it wears little, and since the cleaning blade is constantly pressed against the peripheral surface of the image carrier with a uniform pressure, even if it wears, the image carrier does not wear. In view of the fact that the adhesion to the toner can be maintained for a long period of time, the cleaning effect of the residual toner can be maintained in a good state for a long period of time.

The cleaning device 80 of the above first embodiment
Is a thin blade, and the cleaning blade 81 is held by a cleaning blade holder (holding mechanism) and is brought into uniform contact with the surface of the image carrier 1 by a contact mechanism provided separately. there were. However, in the present invention, since the cleaning blade can be thicker than the cleaning blade 81 of the first embodiment, the structure can be simplified.
This will be described as a second embodiment.

(Second Embodiment) In the second embodiment, a thick cleaning blade is used, and the holding mechanism and the contact mechanism are integrated, and the details thereof will be described.

FIG. 4A is a perspective view of a cleaning device according to the second embodiment of the present invention, and FIG. 4B is a sectional view thereof. In the figure, 81a is a cleaning blade, 810 is a coil spring, 811 is a pressure plate, 812 is a contact piece, 813 is a housing, and 814 is packing.

Similarly to the above, the cleaning blade 81a has a strip shape, but in this embodiment, the cleaning blade 8a.
1a is a plate material thicker than that of the first embodiment,
Moreover, the edge precision is finished well. The material is the same as that of the first embodiment.

When the contact surface side of the image carrier 1 is the front side of the cleaning blade 81a, the free end side edge is formed on the back side (the surface opposite to the contact surface side of the image carrier 1). A rod-shaped contact piece 812 is attached in the vicinity along the longitudinal direction, and a rod-shaped elastic packing 814 is attached along the longitudinal direction on the supporting end side edge.

Reference numeral 813 denotes a housing of the cleaning device, which is made of a long mold material having a V-shaped cross section. This housing 813 is formed with a bulging portion on the surface on the groove side, and a cleaning blade mounting groove 813d is provided therein.
Of the two wall surfaces 813a, 813b of the housing 813, there is a pressure plate mounting wall 813c between the cleaning blade mounting groove 813d and the cleaning blade mounting groove 813d. It is installed in a cantilevered form.

On the free end side of the pressure plate 811, coil springs 810 are inserted with a wall surface 813a of the housing 813 at a predetermined pitch. The cleaning blade 81a is cantilevered in the cleaning blade 81a by fitting the packing 814 portion side attached to the supporting end side edge into the cleaning blade attachment groove 813d. Further, the free end side of the pressure plate 811 is brought into contact with a contact piece 812 provided on the back surface of the cleaning blade 81a at the free end side, whereby the spring force of the coil spring 810 is made to contact the pressure plate 811 and the contact piece 812. Via the cleaning blade 81a, the edge of the cleaning blade 81a on the free end side can be pressed against the surface of the image carrier 1 with a constant pressure.

The cleaning blade 81a is made of a thick metal material which is easy to ensure straightness, and the edge on the free end side thereof has the straightness and the finishing accuracy of the plane in the processing stage. Therefore, the cleaning blade 81a can support the edge on the supporting end side in a fixed manner and press the edge on the free end side against the surface of the image carrier 1, whereby the gap can be suppressed to be equal to or smaller than the particle diameter of the toner. .

With this structure, the cleaning blade unit and the contact mechanism for pressing the cleaning blade can be integrated, and the structure can be simplified. In addition, since the strength can be ensured by adding a pigment to the image carrier 1, it is possible to enhance durability without worrying about occurrence of scratches.

In particular, in this embodiment, the cleaning blade 81a is a relatively thick plate, and there is no fear of deformation of the cleaning blade, and the edges are accurately finished. Since the edge of the cleaning blade can be brought into close contact with the peripheral surface of the image bearing member with no gap by pressing the edge against the image bearing member 1 from the rear, the deformation of the cleaning blade used in the first embodiment is reduced. No cleaning blade holder is needed to do this. Therefore, the cleaning blade holder can be omitted and the structure is simplified.

In any of the present inventions, the cleaning blade is arranged with its free end side edge facing the rotational direction of the image carrier. As in the conventional case, when the cleaning blade is brought into contact with the image bearing member in the counter direction, that is, the blade edge is projected in the direction of rotation of the image bearing member, the blade is attached to the surface of the image bearing member 1. If the edges are brought into contact with each other, the tip of the thin-walled cleaning blade will be warped and the adhesion will be impaired. With the thick-walled cleaning blade, as shown in FIG. 5A, the cleaning blade 8a
As the edge wears, the edge tip becomes sharper,
As shown in FIG. 5B, damage U (peeling cracks) on the edge of the cleaning blade 8a occurs, and as shown in FIG. 5C, burrs V occur on the edge of the cleaning blade 8a, and wear occurs. As a result, the blade edge swelling W may occur due to the small displacement of the blade as shown in FIG.

Since the cleaning blade used in this embodiment is not arranged so as to oppose the rotation direction of the image carrier, the edge of the cleaning blade is in contact with the drum in an elastically deformed state. Therefore, the state shown in FIG. 5 does not occur.

If a slight gap is formed between the edge of the cleaning blade 8a and the image carrier, the toner easily enters in the gap, and once the toner gets into the gap, the wedge effect by the entered toner causes
The blade is easily lifted, and cleaning failure starts from that portion.

However, according to the present embodiment, since the cleaning blade is not arranged so as to oppose the rotation direction of the image carrier, even if the cleaning blade 81a is worn, the cleaning blade will not carry the image. Since the force pressing against the body is applied to the vicinity of the contact point between the image bearing member and the cleaning blade, it is possible to prevent the cleaning blade from curling up and generating vibration,
It is possible to maintain stable cleaning performance for a long period of time.

The present invention is not limited to the above-described embodiments, but can be carried out by appropriately modifying it without departing from the scope of the invention. For example, although the image bearing member has a drum shape in the above-described embodiments, a belt-shaped member may be used, and the cleaning member of the embodiment has a rectangular shape.
Although a strip-shaped one is used, a shape other than a rectangle may be used. Further, the pressure contact force applied near the contact point between the cleaning member and the image carrier may be a part of the pressure contact force to be applied to the contact point.

[0102]

As described above, according to the present invention, even if the edge of the cleaning blade is worn, the cleaning performance is not deteriorated, the stable cleaning performance can be maintained for a long time, and the image bearing property can be maintained. It is possible to provide an electrostatic recording device and a cleaning device therefor capable of enhancing the durability of the body.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the overall configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a cleaning device portion according to the first embodiment of the present invention.

FIG. 3 is a perspective view showing a configuration of a cleaning blade unit including a cleaning blade holder used in the cleaning device according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a cleaning device portion according to a second embodiment of the present invention.

FIG. 5 is a diagram for explaining inconveniences when a thick cleaning blade is used in a conventional configuration.

FIG. 6 is a diagram illustrating a configuration example of a dry electrostatic recording device.

FIG. 7 is a diagram for explaining a configuration example of a dry type laser electrostatic recording apparatus.

FIG. 8 is a diagram for explaining a configuration example of a cleaning device of a conventional system.

FIG. 9 is a diagram for explaining a problem of a conventional cleaning device.

[Explanation of symbols]

1 ... Image carrier 80 ... Cleaning device 81, 81a ... Cleaning blade 83 ... Contact mechanism, 83a ... Support frame 84 ... Metal round bar 85 ... Holding frame 86 ... Blade base 86a, 86b ... Rotation center 87 ... Leaf spring 88 ... Pressing Material 810 ... Coil spring 811 ... Pressure plate 812 ... Contact piece 813 ... Housing 814 ... Packing.

Claims (8)

[Claims] 1. A latent image forming surface is provided, one end side of which is provided in contact with the latent image forming surface of an image carrier that holds a latent image and moves a developing position, and is used for developing a latent image. In a cleaning device of an electrostatic recording device, which removes the residual toner on the supplied image bearing member by scraping it off, a flat surface is formed on at least the contact portion side of the image bearing member with respect to the latent image forming surface of the image bearing member. In addition, a cleaning blade whose contact portion side is inclined to follow the moving direction of the image carrier, and a pressing means for uniformly pressing the cleaning blade toward the image carrier in the vicinity of the contact point with the image carrier. And a cleaning device for an electrostatic recording device. 2. The cleaning device for an electrostatic recording apparatus according to claim 1, wherein the cleaning blade is made of a thin metal plate. 3. The cleaning device for an electrostatic recording apparatus according to claim 1, wherein the cleaning blade is made of a thick metal plate. 4. The cleaning device for an electrostatic recording apparatus according to claim 1, wherein the cleaning blade is made of steel, stainless steel, brass, phosphor bronze, beryllium copper, or ceramic. 5. A latent image forming means, a developing means, a transfer means, and a cleaning means are sequentially arranged around an image carrier which has a drum shape and which has a latent image forming surface on the surface and is rotationally driven, The latent image formed by the image forming unit is converted into a toner image by the developing unit at the developing position, transferred to the recording sheet by the transfer unit at the transfer position, and the residual toner is removed by the cleaning unit at the cleaning position. In the electrostatic recording device, the image carrier uses a resin that holds a latent image,
A pigment is added to the resin, the cleaning means uses a metal plate-shaped cleaning blade, and the tip of the cleaning blade is formed flat, and the latent image is formed on the rotating image carrier. The tip side is inclined with respect to the surface so as to follow the moving direction of the image carrier, the tip is arranged in contact with the latent image forming surface of the image carrier, and the cleaning blade is the contact point with the image carrier. An electrostatic recording apparatus having a structure in which pressure is applied by a pressure unit that uniformly applies pressure to an image carrier in the vicinity. 6. The electrostatic recording apparatus according to claim 5, wherein the cleaning blade is made of a thin metal plate. 7. The electrostatic recording apparatus according to claim 5, wherein the cleaning blade is made of a thick metal plate. 8. The electrostatic recording apparatus according to claim 5, wherein the cleaning blade is made of steel, stainless steel, brass, phosphor bronze, beryllium copper, or ceramic.