JP2000075746A - Cleaning device, process cartridge, and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning device capable of recovering a developer over the entire longitudinal range of a drum cartridge which could cause leakage by enhancing positioning accuracy so that a scooping sheet can surely function at a predetermined end position for the prevention of leakage at a drum cartridge side. SOLUTION: In a cleaning device having a cleaning member 16 for scraping a residual developer remaining on an image carrier carrying a developer image, a storage container 14 for storing the residual developer, a scooping sheet 18 for scooping the developer scraped and for recovering the developer into the storage container, and an end sealant 40 attached to the storage container and located at each end of the cleaning member while making contact with the image carrier, a receiving member 42 for the residual developer is provided below the scooping sheet and the end sealant, the longitudinal width of the receiving member being greater than the longitudinal widths of the scooping sheet and the end sealant combined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device for an image carrier in an electrophotographic system or an electrostatic recording system, and a process cartridge and an image forming apparatus using the same.

[0002]

2. Description of the Related Art In an electrophotographic recording system employed in an image forming apparatus such as a printer or a facsimile, a latent image is formed by exposing an image carrier charged by a charging means, and the latent image is visualized with a developer. Then, this is transferred to a recording medium such as recording paper and fixed there. As the device configuration, the image carrier, charging means, developing means, cleaning section, cleaning container, etc. are integrated into a cartridge to make a cartridge, so that it is possible to exchange parts between the developer and the image carrier, thereby facilitating maintenance. Has been put to practical use.

In recent years, since the life of an image carrier has been prolonged and the number of image forming sheets has tended to increase, the developing means, which limits supply capacity, is provided as an independent unit. , Charging means,
There is a tendency to adopt a cartridge configuration in which the drum unit is divided into two, a cleaning unit and a drum cartridge.

A full-color printer having developing means containing not only one color but also yellow, magenta, cyan, and black developers, such as a monocolor printer, has been put to practical use. Such a full-color printer has a mechanism in which the developing means repeats contact and separation with the image carrier because it is necessary to develop each color developer on the image carrier,
There is a disadvantage that an excessive impact is applied to the image carrier and the developing means at the time of contact. For this reason, it is more difficult to prevent the developer from leaking and scattering. In recent years, in order to obtain a high-definition image, the developer has become finer, and it has become more difficult to prevent leakage as a property of the developer.

[0005] In order to prevent the developer from leaking, it is important for the drum cartridge to first make the rake sheet surely function. Since the rake sheet scoops and collects the developer scraped off by the cleaning member from the image carrier, in order to prevent the developer from leaking from the rake sheet, the mounting accuracy of the rake sheet, especially at the front end position, is increased. It is also necessary to suppress the rake sheet itself from waving. This is because the rake sheet comes into contact with the image carrier and scoops up the developer, and if there is a gap at the contact point, the rake sheet leaks therefrom.

Accordingly, as a configuration for mounting the rake sheet, a means has been adopted in which the rake sheet is mounted on a sheet metal member which is not easily deformed by a change in temperature or an external force, and this sheet metal member is mounted on a cleaning container. In addition, an elastic seal member is disposed in a gap between the sheet metal member and the cleaning container in order to prevent the developer from leaking at this location.

[0007] When the developer leaks from the rake sheet, the leaked developer stains the image, and the image quality may be degraded. For this reason, an end seal may be provided at both ends of the rake sheet to prevent the developer from coming in contact with the image carrier and from the cleaning container, and at the same time, to clean both ends of the image carrier. However, there is a possibility that the developer may spill from the end seal, and a rake receiving member for receiving and storing the developer is provided inside the apparatus.

[0008]

However, when the rake sheet is mounted in the above-described configuration, the rake sheet sheet metal is fixed to the cleaning container by crushing the sealing member. It was thought that a similar warp was reflected in the rake sheet. Therefore, in order to increase the positional accuracy of the rake sheet as compared with the related art, it is necessary to provide the rake sheet metal with sufficient strength in order to suppress deformation.

Conventionally, the rake receiving member is provided mainly on the side of the developing cartridge, and when the rake receiving member is provided on the side of the drum cartridge, it only receives a part of the longitudinal width of the drum cartridge. For this reason, if leakage occurs over the entire longitudinal width, it may be insufficient to receive all the developer.

The present invention solves the above-mentioned problems, and in order to prevent leakage on the drum cartridge side, the positional accuracy is increased so that the rake sheet can function reliably at a predetermined leading end position.
It is a further object of the present invention to provide a cleaning device capable of collecting the developer over the entire longitudinal width of the drum cartridge, which may cause leakage so that the leaked developer does not stain a printed image for safety.

[0011]

In order to solve the above-mentioned problems, a typical configuration of a cleaning device, a process cartridge and an image forming apparatus according to the present invention is to remain on an image carrier for carrying a developer image. A cleaning member for scraping off the developer residue, a storage container for storing the developer residue, a rake sheet for scooping the scraped developer and collecting it in the storage container, and the cleaning device attached to the storage container. A cleaning device having an end seal member located at both ends of the member and contacting the image carrier, further comprising a rake receiving member for the developer residue below the rake sheet and the end seal member. The longitudinal width of the rake receiving member is wider than the longitudinal width including the rake sheet and the end sealing material.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cleaning device according to the present invention will be described with reference to the drawings. 1 is an overall configuration diagram of an image forming apparatus according to the present embodiment, FIG. 2 is a configuration diagram of a drum cartridge according to the present embodiment, FIG. 3 is a front view of a cleaning device, and FIG.
FIG. 5 is a side view of the rake sheet, and FIGS. 6 to 8 are diagrams illustrating details of the periphery of the rake sheet.

[Overall Configuration] An image forming apparatus 1 shown in FIG. 1 is a laser printer which is an embodiment of a color image forming apparatus. As shown in the figure, the image forming apparatus 1 includes an image forming unit including an image carrier 15 rotating at a constant speed, a fixed developing unit 21K, and a rotating developing unit 20 having three color developing units. And an intermediate transfer member 9 for holding the color image developed and superimposed on the recording medium S and further transferring the image to the recording medium S fed from the feeding section. The recording medium S on which the color image has been transferred is conveyed to the fixing unit 25 and fixed by applying heat and pressure, and is discharged by a discharge roller on the upper surface of the apparatus by a discharge roller.
Discharge to 37. In addition, the rotatable color developing unit and the fixed black developing unit are configured to be individually detachable from the main body of the image forming apparatus 1. Next, the configuration of each section of the image forming apparatus 1 will be sequentially described in detail.

The drum cartridge 13 includes an image carrier 15 and
This is configured integrally with the cleaning container 14 also serving as a holder for the image carrier 15. This drum cartridge
The image carrier 15 is detachably supported with respect to the apparatus main body.
The unit can be easily replaced according to the life of the unit. In the present embodiment, the image carrier 15 is formed by applying an organic photoconductor layer to the outside of an aluminum cylinder having a diameter of about 60 mm, and is rotatably attached to the cleaning container 14.
A cleaner blade 16 serving as a cleaning member and a primary charging unit 17 are arranged on the periphery of the image carrier 15, and are driven to rotate in accordance with an image forming operation by a driving force of a driving motor (not shown). The cleaning container 14 will be described later.

The primary charging means 17 uses a contact charging method, in which a conductive roller is brought into contact with the image carrier 15. By applying a voltage to the conductive roller, the surface of the image carrier 15 can be uniformly charged.

Exposure to the image carrier 15 is performed by a scanner unit 30.
Done from That is, when an image signal is given to the laser diode, the laser diode irradiates the polygon mirror 31 with image light corresponding to the image signal. The polygon mirror 31 is rotated at high speed by a scanner motor (not shown), and the image light reflected by the polygon mirror 31 selectively exposes the surface of the image carrier 15 rotating at a constant speed via the imaging lens 32 and the reflection mirror 33. As a result, an electrostatic latent image is formed on the image carrier.

The developing means includes a yellow developing means 20Y, a magenta developing means 20M, and a developing means for visualizing the electrostatic latent image.
It comprises a rotary developing unit 20 having each color developing unit of the cyan developing unit 20C, and one black developing unit 21K.

The black developing means 21K is a fixed developing means. A sleeve 21KS is arranged at a position facing the image carrier 15 at a small distance from the image carrier 15, and the image carrier 15 is made of black toner. Form a visual image. The black developing means 21K feeds the toner in the container by a feed mechanism, applies a thin layer of toner to the outer circumference of the sleeve 21KS rotating clockwise in the figure by an application blade 21KB pressed against the outer circumference of the sleeve 21KS, and transfers electric charges to the toner. Give. Further, by applying a developing bias to the sleeve 21KS, toner development is performed corresponding to the electrostatic latent image on the image carrier 15.

The rotary developing means 20 is detachably supported by a developing rotary 23 which rotates about a shaft 22. Each of the developing means rotates about the shaft 22 when forming an image.
The rotation is stopped at a position where a predetermined developing unit faces the image carrier 15. Furthermore, after positioning the sleeves 20YS, 20MS, and 20CS so that they face the image carrier 15 at a small interval (about 300 μm), a visible image is formed corresponding to the electrostatic latent image on the image carrier 15 I do. At the time of forming a color image, the developing rotary 23 rotates every one rotation of the intermediate transfer body 9, and the yellow developing unit 20 Y, the magenta developing unit 20 M, the cyan developing unit 20 C,
Next, the developing process is performed in the order of the black developing means 21K, and the image is transferred to the intermediate transfer body 9 for each color and superimposed. The developer residue remaining on the image carrier 15 after transferring the toner image to the intermediate transfer member 9, that is, waste toner is removed by a cleaning unit described later.

FIG. 1 shows a state in which the yellow developing means 20Y is positioned stationary at a position facing the image carrier unit. The yellow developing means 20Y sends the toner in the container to the coating roller 20YR by a feeding mechanism, and applies a thin film of the toner to the outer circumference of the sleeve 20YS rotating clockwise by the coating roller 20YR and the blade 20YB rotating clockwise in the drawing. And charge is applied to the toner (frictional charging)
I do. Then, by applying a developing bias to the sleeve 20YS facing the image carrier 15 on which the latent image is formed, toner development is performed on the image carrier 15 in accordance with the latent image. Similarly, magenta developing means 20M and cyan developing means 20C form images of respective colors.

Further, sleeves 20YS and 20M of each rotary developing means are provided.
The S and 20CS are connected to a high-voltage power supply for each color development and a drive provided in the printer main body when each developing unit is rotated to the developing position, and is driven by sequentially applying a voltage to each color developing unit selectively. Is connected.

The intermediate transfer body 9 rotates clockwise in the figure in synchronization with the outer peripheral speed of the image carrier 15, and when a color image is formed, the toner image on the image carrier 15 visualized by each developing means is printed four times (CMYK). (Each image of four colors). Further, the intermediate transfer body 9 that has undergone the multiple transfer transfers the color toner image on the intermediate transfer body 9 to the recording medium S collectively by nipping and conveying the recording medium S with the transfer roller 10 to which a voltage is applied.

The intermediate transfer member 9 according to the present embodiment has a diameter of 180 m.
The outer circumference of an aluminum cylinder 12 of m m is covered with an elastic layer 11 such as a medium resistance sponge or medium resistance rubber. The intermediate transfer member 9 is rotatably supported, and is driven to rotate by a gear (not shown) which is integrally fixed and rotates.

The recording medium S is loaded on a cassette 2 provided below the apparatus main body. The recording medium S is sent out by a pickup roller 3 and separated by a feed roller 4 and a retard roller 5 one by one. The sheet is guided and guided to the registration roller 8. The registration roller 8 corrects the skew of the recording medium S by performing a non-rotating operation of stopping the recording medium S in a standby state and a rotating operation of transporting the recording medium S toward the intermediate transfer body 9 in a predetermined sequence. At the same time, the recording medium S is conveyed in synchronization with the intermediate transfer member 9.

The intermediate transfer body 9 is provided with a transfer roller 10 having a medium-resistance foamed elastic body wound around a metal shaft so as to be able to be separated from and brought into contact with the transfer roller.
While the transfer roller 10 is forming a four-color toner image on the intermediate transfer member 9, that is, while the intermediate transfer member 9 rotates a plurality of times, the intermediate transfer member 10 is not disturbed as shown by a solid line in the drawing. 9 away. When the recording medium S is conveyed after the formation of the color toner image on the intermediate transfer member 9, a predetermined cam is applied to the intermediate transfer member 9 via the recording medium S by a cam (not shown) as shown by a broken line in FIG. Energized by pressure.

At this time, a bias is simultaneously applied to the transfer roller 10, and the toner image on the intermediate transfer member 9 is transferred to the recording medium S. Here, since the intermediate transfer member 9 and the transfer roller 10 are each driven, the recording medium S sandwiched between the two is driven.
Is performed at the same time as the transfer process is performed,
At a predetermined speed.

The fixing unit 25 fixes the toner image transferred onto the recording medium S, and includes a fixing roller 26 for applying heat and a pressure roller for pressing the recording medium S against the fixing roller 26. It consists of 27. Each roller
Reference numerals 26 and 27 denote hollow rollers, each having heaters 28 and 29 therein, and configured to convey the recording medium S by being rotationally driven.

That is, the recording medium S holding the toner image is conveyed by the fixing roller 26 and the pressing roller 27 and is applied with heat and pressure, so that the toner image is fixed on the recording medium S. The recording medium S on which the image has been fixed is conveyed by the conveyance rollers 34 and the conveyance rollers 35, discharged and stacked on the discharge unit 37 by the discharge rollers 36, and the image formation is completed.

[Cleaning container] Drum cartridge
The 13 cleaning containers 14 will be described with reference to FIG. As described above, the drum cartridge 13 includes the image carrier 15 and the cleaning container 14, and the image carrier 15
The waste toner removed from the cleaning container is stored in the cleaning container 14. The amount of waste toner stored in the cleaning container 14 is not filled earlier than the life of the image carrier 15,
When the life of the image carrier 15 is replaced, the replacement is performed integrally.

The cleaning process is performed by a cleaner blade 16 attached to the cleaning container 14 and a cleaning brush 19. The waste toner on the image carrier 15 passes through the rake sheet 18 and enters the cleaning container 14, and is scraped off by the cleaning brush 19 and then by the cleaner blade 16. The scraped-off waste toner is scooped by the rake sheet 18 and collected in the cleaning container 14. Cleaning brush
The waste toner that has entered the inside 19 is scraped off by the scraper 38 and deposited. The accumulated waste toner is transported to the inner side of the cleaning container 14 by the screw 39.

As shown in FIG. 3, end seals 40 are provided at both ends of the cleaner blade 16 and are attached to the cleaning container 14. The end seal 40 contacts the image carrier 15 to prevent toner from leaking from the cleaning container 14 and also cleans the end of the image carrier 15 at the same time. As shown in FIG. 4, the end seal 40 has two layers, and includes a surface layer 47 in which fibers are planted on a sheet and abuts on the image carrier 15, and a foam layer 48 for obtaining elasticity.

The rake sheet 18 is located at the opening 49 of the cleaning container 14 and collects toner. As shown in FIG. 6, the rake sheet 18 is attached to a rake sheet metal 41. A rake receiving member 42 including a rake receiving sheet 43 and a rake receiving metal plate 44 is disposed below the rake sheet 18. The rake receiving member 42 is fixed to the rake sheet metal 41 and is used for reinforcing the rake sheet metal 41.

As shown in FIG. 5, the rake sheet metal 41 is attached to the cleaning container 14 via a seal member 45. The sealing member 45 is formed of a foam, and its longitudinal width extends over the entire longitudinal width of the rake sheet metal 41. Seal member
The thickness of 45 is larger than the gap between the rake sheet metal 41 and the cleaning container 14, and is crushed when the rake sheet metal 41 is attached, and exerts pressure on the rake sheet metal 41. However, since the rake sheet metal 41 is reinforced by the rake receiving member 42 here, no warpage occurs, and high positional accuracy can be secured over the entire longitudinal width.

As shown in FIG. 3, the longitudinal width α of the rake receiving sheet 43 and the rake receiving sheet metal 44 is different from that of the rake sheet 18.
The waste toner that leaks out of the cleaning container 14 and is spilled from the cleaning container 14 can be collected without being covered over the entire longitudinal width.

As shown in FIG. 5, the rake receiving member 42
Of the rake sheet 18 and the image carrier 15 is located on the image carrier side with respect to a line vertically lowered from the contact point 51 between the rake sheet 18 and the image carrier 15. As a result, the waste toner spilled from the contact point 51 can be reliably collected in the collection space 46 formed by the rake receiving sheet 43 and the rake receiving sheet metal 44.

[0036]

As described above, in the cleaning device according to the present invention, since the receiving member having a width larger than the longitudinal width of the rake sheet and the end sealing material is disposed below the rake sheet, the developer remains. Objects do not spill and do not stain the recording medium.

By fixing the rake sheet metal of the rake receiving member to the rake sheet metal of the rake sheet, the rake sheet metal could be easily reinforced without increasing the number of parts. As a result, the rake sheet metal can be prevented from warping due to the pressure from the lower seal member, and the positional accuracy can be secured over the entire longitudinal width so that the rake sheet can function reliably at a predetermined position.

Further, since the tip of the rake receiving member is disposed closer to the image carrier than vertically below the contact point between the rake sheet and the image carrier, the developer residue spilled from the contact can be reliably collected. In addition, it is possible to further reduce the stain on the recording medium.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an image forming apparatus according to an embodiment.

FIG. 2 is a configuration diagram of a drum cartridge according to the present embodiment.

FIG. 3 is a front view of the cleaning device.

FIG. 4 is a diagram illustrating an end seal.

FIG. 5 is a side view of a rake sheet.

FIG. 6 is a diagram illustrating details of the periphery of a rake sheet.

FIG. 7 is a diagram illustrating details of the periphery of a rake sheet.

FIG. 8 is a diagram illustrating details of the periphery of a rake sheet.

[Explanation of symbols]

 S ... recording medium 1 ... image forming apparatus 2 ... cassette 3 ... pickup roller 4 ... feeding roller 5 ... retard roller 6 ... paper feed guide 8 ... registration roller 9 ... intermediate transfer body 10 ... transfer roller 11 ... elastic layer 12 ... aluminum Cylinder 13 Drum cartridge 14 Cleaning container 15 Image carrier 16 Cleaner blade 17 Primary charging means 18 Rake sheet 19 Cleaning brush 20 Rotary developing means 20C Cyan developing means 20M Magenta developing means 20Y Yellow developing Means 21K: Black developing means 22: Axis 23: Development rotary 25: Fixing unit 26: Fixing roller 27: Pressure roller 28: Heater 29: Heater 30: Scanner unit 31: Polygon mirror 32: Image forming lens 33: Reflecting mirror 34 … Convey roller 35… Convey roller 36… Discharge roller 37… Discharge part 38… Scraper 39… Screw 40 ... end seal 41 ... rake sheet metal 42 ... rake receiving member 43 ... rake receiving sheet 44 ... rake receiving sheet metal 45 ... seal member 46 ... collection space 47 ... surface layer 48 ... foam layer 49 ... opening 50 ... tip 51 ... contact

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kazunari Murayama 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2H034 BA01 BD00 BF00 CA04

Claims (5)

[Claims] 1. A cleaning member for scraping off a developer residue remaining on an image carrier for carrying a developer image, a storage container for storing the developer residue, and scooping the scraped developer. A cleaning apparatus comprising: a rake sheet to be collected in the storage container; and an end sealing member attached to the storage container and positioned at both ends of the cleaning member and in contact with the image carrier. A cleaning device having a rake receiving member for the developer residue below a part sealing material, wherein a longitudinal width of the rake receiving member is wider than a longitudinal width including the rake sheet and the end sealing material. . 2. A cleaning member for scraping off a developer residue remaining on an image bearing member carrying a toner image after transfer, a storage container for storing the developer residue, and scooping the scraped developer. A cleaning apparatus comprising: a rake sheet to be collected in the storage container, a sheet metal member attached to the storage container to support the rake sheet, and a seal member disposed between the storage container and the sheet metal member. A cleaning device comprising a rake receiving member for the developer residue below a rake sheet, wherein the sheet metal member is reinforced by attaching the rake receiving member to the sheet metal member. 3. An image carrier side end of the rake receiving member is located closer to the image carrier than vertically below a contact point between the rake sheet and the image carrier. The cleaning device according to claim 1 or 2. 4. A process cartridge for an image forming apparatus, comprising: an image carrier for carrying at least a developer image; and the cleaning device according to claim 1. 5. An image carrier for forming an electrostatic latent image, developing means for developing the electrostatic latent image to visualize a developer image, and a recording medium for transferring the developer image from the image carrier. 4. An image, comprising: a transfer unit that transfers the developer to the image carrier; and a cleaning device according to claim 1, which cleans a developer residue remaining on the image carrier after the transfer. Forming equipment.