JPH11272071A - Developing device, processing cartridge and electrophotographic image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a sealing performance to the toner between a developing roller or a photoreceptor drum and a cartridge frame body. SOLUTION: An end part periphery sealing member 105 and a back-sealing 106 can not be structurally integrated into one body. Accordingly, or otherwise, in order to seal by letting respective sealing member being made of different material held in contact with each other, tone developing device is made so as possible to improve the sealing performance, by pressing one of or every sealing member in a projecting shape 106c, the recessing shape, the non-parallel shape, and or the shape provided with a curve with respect to the plane desired to be sealed, compressing the projecting shape, the recessing shape, the non- parallel shape or the shape provided with the curve, and imparting an effect derived from the labyrinth groove 106e in increasing close contact property.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a developing device and a process cartridge used for an electrophotographic image forming apparatus such as a copying machine and a printer.

[0002]

2. Description of the Related Art An image forming apparatus such as a printer using an electrophotographic process uniformly charges a photosensitive drum serving as an image carrier and forms a latent image by selectively exposing the photosensitive drum. , The latent image is revealed by toner as a developer,
The toner image is transferred to a recording medium, and heat and pressure are applied to the transferred toner image to fix the toner image on the recording medium, thereby performing image recording.

Conventionally, in an image forming apparatus using an electrophotographic image forming process, an electrophotographic photosensitive member and a process means acting on the electrophotographic photosensitive member are integrally made into a cartridge, and this cartridge is attached to a main body of the image forming apparatus. A detachable process cartridge system is employed. According to this process cartridge system, the maintenance of the apparatus can be performed by the user himself without relying on a serviceman, so that the operability can be remarkably improved. Therefore, this process cartridge system is widely used in image forming apparatuses.

A developing device in which a developing means is integrally formed as a cartridge as a process means and this cartridge is detachably mountable to a main body of the image forming apparatus is widely used in a multicolor image forming apparatus.

[0005] In such an apparatus, a developing roller as a means for supplying a toner stored in a developing frame to a photosensitive drum is provided as a developing means for providing a latent image, and a developing roller for supplying toner to the developing roller. A developing blade that regulates the amount of toner to be applied, an end peripheral surface sealing member formed of felt or the like at both ends of an opening of the developing frame to prevent developer from leaking in the lateral direction of the developing roller, and a developing frame. A developing blade around the opening and a back seal member for filling a gap between the developing frame are provided. A sheet member for preventing the developer from blowing out from a gap generated between the lower portion of the developing roller and the opening is provided at a lower portion.

The sheet member is attached to the lower part of the opening of the developing frame, and one end in the short direction is a free end. A part of this free end is in contact with the peripheral surface of the entire length of the developing roller (axial direction of the developing roller).

On the other hand, the length of the sheet member extends to a position where the sheet member overlaps the end peripheral surface sealing member, thereby preventing toner from blowing out from the gap.

In the case of cleaning means for removing toner remaining after transfer on the photosensitive drum, a sealing member for sealing a gap between the photosensitive drum and the opening of the cleaning frame is provided.

[0009]

In the above prior art,
A back seal member for filling a gap between the developing blade and the developing frame 101 is fixed to the developing frame so as to be located on the upper surface of the opening of the developing frame and on the back side of the developing blade. An end peripheral surface sealing member of the developing device is disposed between the developing roller and the developing frame on both sides of the developing blade. The seal member is generally made of a flexible material such as a felt flock material, and is fixed to the developing frame.

Here, the seal member and the back seal member are arranged in close contact with each other, and seal the toner conveyed from the developing container to the developing system at the opening of the developing frame.

However, in recent years, toner having a high particle size in pursuit of high image quality has been used in many cases, and the toner enters the close contact portion between the end peripheral sealing member and the back sealing member to lower the sealing performance. Toner may leak so as to pass through the contact portion.

The present invention is a further development of the prior art, and has as its object to provide a developing device and a process cartridge in which the sealing performance between the end peripheral surface sealing member and the back sealing member is improved.

[0013]

The main aspects of the present invention are as described below with reference to the claims.

According to a first aspect of the present invention, there is provided a developing device which is detachable from an image forming apparatus main body and which uses a toner to develop a latent image formed on an electrophotographic photosensitive drum using a toner. Or, a developing roller disposed with a gap, a developing frame supporting the developing roller and forming a toner container, a developing blade fixed to the developing frame and elastically in contact with a peripheral surface in a longitudinal direction of the developing roller, A sheet member fixed to the developing frame and in contact with the peripheral surface in the longitudinal direction of the developing roller; an end peripheral surface sealing member that is held by the developing frame and seals both peripheral surfaces at least between the developing blade and the sheet member of the developing roller; A back seal member provided on the back surface of the developing blade and having an end surface in contact with the side surface of the end peripheral surface seal member, wherein the back seal member is a single unit at the end. A protrusion is provided on a part of the end face so as to protrude in the longitudinal direction. In the assembled state, the protrusion is pressed against the end peripheral seal member so as to be crushed and the both end surfaces are in contact with the side surface of the end peripheral seal member. A projecting portion of the back seal member in a unitary state protrudes outside the opposite side surface of the end peripheral surface seal member.

According to an eighth aspect of the present invention, there is provided a process cartridge detachably mountable to an image forming apparatus main body, wherein an electrophotographic photosensitive drum and a latent image formed on the electrophotographic photosensitive drum are developed using toner. Developing means,
Wherein the developing means has a developing roller disposed in contact with or at a gap from the electrophotographic photosensitive drum, a developing frame supporting the developing roller and forming a toner container, and a developing roller fixed to the developing frame. A developing blade elastically in contact with the generating line of the developing roller, a sheet member fixed to the developing frame and in contact with the peripheral surface in the longitudinal direction of the developing roller, and a peripheral surface held at both ends at least between the developing blade and the sheet member of the developing roller. An end peripheral surface sealing member to be sealed, and a back seal member provided on the back surface of the developing blade and having an end surface in contact with a side surface of the end peripheral surface sealing member,
The back seal member is provided with a protruding portion projecting in a longitudinal direction at a part of both end surfaces at an end portion of the single unit, and in the assembled state, the protruding portion is pressed against the end peripheral surface sealing member and crushed, and the both end surfaces are A process cartridge characterized in that a convex portion of a back seal member in a unitary state protrudes outside the opposed side surface of the end peripheral surface seal member so as to contact the side surface of the end peripheral seal member.

According to a ninth aspect of the present invention, there is provided a process cartridge detachably mountable to an image forming apparatus main body, comprising: an electrophotographic photosensitive drum; and a cleaning means for removing toner remaining after transfer on the electrophotographic photosensitive drum. ,
A cleaning member that contacts the electrophotographic photosensitive drum and removes toner remaining on the electrophotographic photosensitive drum after transfer; and a cleaning member that supports the electrophotographic photosensitive drum and removes the toner from the electrophotographic photosensitive drum. A cartridge frame forming a toner reservoir for storing the removed toner, a squeeze sheet fixed to the cartridge frame and elastically contacting the peripheral surface in the longitudinal direction of the electrophotographic photosensitive drum, and both ends of the electrophotographic photosensitive drum held by the cartridge frame An end peripheral surface sealing member for sealing the peripheral surface,
A back seal member provided on the back surface of the cleaning member and having an end surface in contact with the side surface of the end peripheral surface seal member, wherein the back seal member is a single-unit projecting portion projecting in a longitudinal direction at a part of both end surfaces at an end portion. In the assembled state, the convex portion is pressed against the end peripheral surface sealing member so as to be crushed, and between the opposite side surfaces of the end peripheral surface sealing member such that the both end surfaces are in contact with the side surfaces of the end peripheral sealing member. A process cartridge characterized in that a convex portion of a back seal member in a unitary state protrudes outside the distance of.

According to a fifteenth aspect of the present invention, there is provided an electrophotographic image forming apparatus having a container for accommodating a toner, and a plurality of seal members arranged to abut each other to seal an opening of the container. A photographic photoreceptor drum, a process unit acting on the electrophotographic photoreceptor drum, a transfer unit for transferring a toner image formed on the electrophotographic photoreceptor drum to a recording medium, and a transfer unit for transferring the recording medium ,
A conveying unit that discharges the image forming apparatus out of the main body through the fixing unit; and the fixing unit. A part of the one seal member facing the other seal member at a portion where the plurality of seal members abut. A convex portion is provided in the portion, and the convex portion is crushed and contacts the other seal member together with the surface,
An electrophotographic image forming apparatus, wherein a labyrinth groove is formed at a portion corresponding to a corner between a root of a convex portion and the surface.

[0018]

(Embodiment 1) An embodiment of the present invention will be described with reference to the following drawings.

[Overall Description of Electrophotographic Image Forming Apparatus] First, the overall configuration of a color electrophotographic image forming apparatus will be schematically described with reference to FIG.

FIG. 1 is an explanatory view of the overall configuration of a laser printer which is an embodiment of a color electrophotographic image forming apparatus.

As shown in FIG. 1, a color laser printer is a photosensitive drum 1 serving as an image carrier which rotates at a constant speed.
5 and three color developing devices 20Y and 20 rotatable indexably with respect to the black developing device 21B and the photosensitive drum 15.
M and 20C, and an intermediate transfer member 9 for holding a color image developed and multiplex-transferred in the image forming unit and further transferring the color image to the transfer material 2 fed from the feeding unit.
The transfer material 2 onto which the color image has been transferred is then conveyed to the fixing unit 25 to fix the color image on the transfer material 2 and discharged to discharge units 37 on the upper surface of the apparatus by discharge rollers 34, 35, and 36. The index developing rotatable color developing devices 20Y, 20M and 20C and the fixed black developing device 21B
Are detachably attached to the main body 18 of the electrophotographic image forming apparatus.

Next, the configuration of each section of the electrophotographic image forming apparatus will be sequentially described in detail.

[Process Cartridge] The process cartridge 13 integrally includes a photosensitive drum 15, a cleaning blade 16, a primary charging unit 17, and a cleaning container 14 also serving as a holder for the photosensitive drum 15. The process cartridge 1 is detachably supported on the main body 18 of the electrophotographic image forming apparatus, and easily fits the life of the photosensitive drum 15.
It is configured so that every three can be replaced. The photoconductor drum 15 according to the present embodiment is formed by applying an organic photoconductor layer to the outside of an aluminum cylinder, and is rotatably supported by a cleaning container 14 also serving as a holder for the photoconductor drum 15. In the cleaning container 14, a cleaning blade 16 and a primary charging unit 17 are arranged on the periphery of the photoconductor drum 15, and the photoconductor drum 15 is partially exposed to the outside of the cleaning container 14. In addition, by transmitting the driving force of a drive motor (not shown) to one end behind the illustrated photosensitive drum 15, the photosensitive drum 15 is rotated counterclockwise in the figure according to the image forming operation.

The primary charging means 17 provided in the process cartridge 13 employs a contact charging method, in which a conductive roller is brought into contact with the photosensitive drum 15 and a voltage is applied to the conductive roller to thereby charge the photosensitive drum. This is to uniformly charge the surface of the drum 15.

The process cartridge is a cartridge in which a charging unit, a cleaning unit, and an electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachable from an electrophotographic image forming apparatus main body. In addition, at least one of the charging means and the cleaning means and the electrophotographic photosensitive member are integrally formed into a cartridge so that the cartridge can be attached to and detached from the electrophotographic image forming apparatus main body.

[Exposure Means] Exposure to the photosensitive drum 15 is performed from the scanner unit 30. 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 a high speed by a scanner motor, and the image light reflected by the polygon mirror 31 selectively exposes the surface of the photosensitive drum 15 rotating at a constant speed through the imaging lens 32 and the reflection mirror 33 to thereby expose the surface. As a result, an electrostatic latent image is formed on the photosensitive drum 15.

[Developing Units] The developing units 20 and 21 are provided for yellow, magenta,
Three developing units 20 capable of developing each color of cyan and black
Y, 20M, 20C and one black developing unit 21B. The developing means 20 will be described in more detail later.

The black developing unit 21B of the developing means 21 is a fixed developing unit, and a developing roller 21BS as a developer carrier is disposed at a position opposed to the photosensitive drum 15 at a minute interval from the photosensitive drum 15. A toner image is formed on the drum 15 using black toner.

The black developing device 21B feeds the toner in the container by a feed mechanism 21BT, and a thin layer of toner is formed on the outer periphery of the developing roller 21BS which rotates clockwise in FIG. 1 by a developing blade 21BB pressed against the outer periphery of the developing roller 21BS. Apply and charge (frictional charging) the toner. Further, by applying a developing bias to the developing roller 21BS, toner is supplied to the photosensitive drum 15 to perform toner development corresponding to the electrostatic latent image on the photosensitive drum 15.

[Sheet Feeding Section] The sheet feeding section transfers the transfer material 2 to the image forming section.
And a feed roller 3, a feed roller 4, a retard roller 5 for preventing double feed, a paper feed guide 6, and a registration roller 8. It is composed of During image formation, the paper feed roller 3 is driven and rotated in accordance with the image forming operation, separates and feeds the transfer material 2 in the paper feed cassette 1 one by one, and is guided by the paper feed guide 6 via the transport roller 7. To the registration roller 8. During the image forming operation, the registration roller 8 performs a non-rotating operation of stopping the transfer material 2 in a standby state and a rotating operation of transporting the transfer material 2 toward the intermediate transfer body 9 in a predetermined sequence, which is the next step. The image and the transfer material 2 at the time of the transfer step are aligned.

[Transfer Section] The transfer section comprises a swingable transfer roller 10.

The transfer roller 10 has a metal shaft wound around a medium-resistance foamed elastic material, is movable up and down in the figure, and rotates by receiving a driving force. While forming the four-color toner image on the intermediate transfer member 9, that is, while the intermediate transfer member 9 rotates a plurality of times, the transfer roller 10 is positioned below as shown by a solid line in the drawing so as not to disturb the image. It is separated from the intermediate transfer member 9.
After the four color toner images have been formed on the intermediate transfer member 9, the transfer roller 10 is moved by a cam member (not shown) to an upper position indicated by a thin line in FIG. It is pressed against the intermediate transfer body 9 via the material 2 with a predetermined pressure. At this time, a bias is applied to the transfer roller 10 at the same time, and the toner image on the intermediate transfer body 9 is transferred to the transfer material 2. Here, since the intermediate transfer member 9 and the transfer roller 10 are driven respectively, the transfer material 2 sandwiched between the two is transferred at a predetermined speed to the left in the figure at the same time as the transfer process is performed, and is transferred to the next process. Is sent to the fixing unit 25.

[Fixing Section] The fixing section 25 is provided with the developing means 2
The toner image formed on the transfer material 2 is fixed on the transfer material 2 via the intermediate transfer member 9 with the toner image formed by the transfer media 0 and 21. As shown in FIG. A roller 26 and a pressure roller 27 for pressing the transfer material 2 against the fixing roller 26. Each roller is a hollow roller and has a heater 28, 2 inside.
9 and is configured to be driven to rotate and to simultaneously transfer the transfer material 2.

That is, the transfer material 2 holding the toner image is conveyed by the fixing roller 26 and the pressure roller 27 and is subjected to heat and pressure so that the toner is transferred to the transfer material 2.
Is established.

[Image Forming Operation] Next, a description will be given of an operation in the case where an image is formed by the apparatus configured as described above.

First, the paper feed roller 3 shown in FIG. 1 is rotated to separate one transfer material 2 in the paper feed cassette 1, and is conveyed to the registration roller 8.

On the other hand, the photosensitive drum 15 and the intermediate transfer member 9 are driven and rotated at the same outer peripheral speed in the direction of the arrow shown in the figure.

The developing means 20 comprises three developing units 20Y and 20
M and 20C are detachably held by a developing rotary 23 which rotates at an angle of 120 degrees and an intermediate point about a center shaft 22. When forming an image, the center of each developing unit is held by the developing rotary 23. Shaft 22
Is rotated about the photosensitive drum 1
5 and the developing roller 20YS,
(The developing devices 20M and 20C are not denoted by reference numerals in the drawings.
Are positioned so as to face the photosensitive drum 15 at a small interval (about 300 μm), and then a visible image corresponding to the electrostatic latent image on the photosensitive drum 15 is formed. Form. At the time of forming a color image, the developing rotary 23 rotates for each rotation of the intermediate transfer body 9, and the yellow developing device 20Y, the magenta developing device 20M,
The developing process is performed in the order of the cyan developing device 20C and then the black developing device 21B.

The developing units 20Y, 20M, and 20C are provided with a developing roller for applying toner to the photosensitive drum 15, an application roller for sending toner from the toner container to the developer roller, and a constant toner layer thickness on the developing roller. A developing blade and a toner container accommodating toner in a frame to form an integral cartridge.
The developing cartridge 3 is detachable from the developing cartridge 3.

FIG. 1 shows a state in which the yellow developing unit 20Y is stationary at a position facing the process cartridge 13. The yellow developing device 20Y is fed to the coating roller 20YR by a toner feeding mechanism 20YT in the toner container, and is rotated clockwise by a coating blade 20YR rotating clockwise and a developing blade 20YB pressed against the outer periphery of the developing roller 20YS. A thin layer of toner is applied to the outer periphery of the toner, and a charge is applied to the toner (frictional charging). By applying a developing bias to the developing roller 20YS facing the photosensitive drum 15 on which the latent image is formed, toner development is performed on the photosensitive drum 15 in accordance with the latent image. In the magenta developing device 20M and the cyan developing device 20C, toner development is performed by the same mechanism as described above.

The developing rollers of the developing units 20Y, 20M and 20C are used for developing the respective colors provided on the main body 18 of the electrophotographic image forming apparatus when the developing units 20Y, 20M and 20C are indexed to the developing positions and rotated. The driving member is connected to a high-voltage power supply and a drive, and a voltage is sequentially and selectively applied for each color development to connect the driving member.

[Intermediate Transfer Body] The intermediate transfer body 9 is used for each of the developing units 20Y, 20M, 20C, 21 during the color image forming operation.
B, the toner image on the photosensitive drum 15 visualized four times (4 times of yellow Y, magenta M, cyan C, and black B).
In order to receive the multiple transfer over each color toner image), the intermediate transfer member 9 rotates clockwise in synchronization with the outer peripheral speed of the photosensitive drum 15 and the intermediate transfer member 9 that has received the multiple transfer is connected to the transfer roller 10 to which the voltage is applied. The transfer material 2 is sandwiched and conveyed, whereby the respective color toner images on the intermediate transfer body 9 are simultaneously multiplex-transferred onto the transfer material 2.

The intermediate transfer member 9 according to the first embodiment has a structure in which the outer periphery of an aluminum cylinder 12 is covered with an elastic layer 11 such as a medium resistance sponge or medium resistance rubber. The intermediate transfer body 9 receives a driving force from a gear (not shown) which is rotatably supported and integrally fixed, and rotates.

[Cleaning Means] The cleaning blade 16 is integrally incorporated into the above-described process cartridge 13 so as to be in pressure contact with the generatrix of the photosensitive drum 15, and the toner visualized on the photosensitive drum 15 by the developing means is removed. After being transferred to the intermediate transfer member 9, the toner remaining on the photosensitive drum 15 is scraped off and cleaned.
4 The amount of waste toner stored in the container 14 does not fill the container 14 earlier than the life of the photosensitive drum 15, and therefore, the cleaning container 14 is simultaneously replaced when the photosensitive drum 15 is replaced due to its life. You.

When an arbitrary point on the outer periphery of the illustrated intermediate transfer member 9 reaches the position S in the figure, the photosensitive drum 15 whose surface has been uniformly charged by the charging means 17 is subjected to laser exposure at the position E in the figure. An image is formed. The distance from the exposure position E of the photoconductor drum 15 to the first transfer position T1, which is a contact portion with the intermediate transfer member 9 counterclockwise, and the distance from the illustrated S point of the intermediate transfer member 9 to the first transfer position T1 are: After the lapse of time, the point E at the start of writing the image and the point S on the intermediate transfer member 9 are equal.
At the first transfer position T1. That is, an image is formed counterclockwise with respect to the intermediate transfer member 9 with the point S as a tip.

1: Formation of Yellow Image Laser irradiation of the yellow image is performed by the scanner unit 30 to form a yellow latent image on the photosensitive drum 15.
Simultaneously with the formation of the latent image, the yellow developing device 20Y is driven to apply a voltage having the same polarity and substantially the same potential as the charging polarity of the photoconductor drum 15 so that yellow toner adheres to the latent image on the photoconductor drum 15, and the yellow image is formed. Perform development. At the same time, the yellow toner image on the photosensitive drum 15 is primarily transferred to the outer periphery of the intermediate transfer member 9 at a first transfer position T1 slightly downstream of the developing section. At this time, a voltage having a polarity opposite to that of the yellow toner is applied to the intermediate transfer member 9 to perform primary transfer.

When the image to be formed is, for example, A3 size of Japanese Industrial Standard paper, L1 from the outer peripheral point S of the intermediate transfer member 9
When the transfer of the yellow toner to the intermediate transfer member 9 is completed, that is, the point L1 is at the first transfer position T1. , The developing rotary 23 rotates clockwise, and the next magenta developing device 20M rotates and is positioned at a position facing the photosensitive drum 15.

2: Formation of Magenta Image Next, when one point on the outer periphery of the intermediate transfer member 9 (the tip of the yellow image) makes a circuit and reaches the position of the point S in the drawing, the scanner unit 30 similarly applies laser irradiation of the magenta image. The magenta toner image is developed on the latent image on the photosensitive drum 15 in the same manner as in the case of yellow, and the magenta toner image on the photosensitive drum 15 is similarly transferred onto the intermediate transfer body 9 at the first transfer position T1. . When the transfer of the magenta toner to the intermediate transfer member 9 is completed, that is, when the point L1 has passed the first transfer position T1, the developing rotary 23 rotates clockwise, and the next cyan developing device 20C rotates, and the photosensitive drum 20C rotates. 15 are positioned.

3: Formation of Cyan Image Next, when one point on the outer periphery of the intermediate transfer member 9 (the leading end of the yellow and magenta images) makes another round and reaches the position of the point S in the drawing, the scanner unit 30 similarly forms the cyan image. Laser irradiation is performed, and the photosensitive drum 15
A cyan toner image is developed on the upper latent image, and the photosensitive drum 1
5 is transferred onto the intermediate transfer member 9 at the first transfer position T1 so as to overlap the yellow and magenta toner images. When the transfer of the cyan toner image to the intermediate transfer member 9 is completed, that is, when the point L1 has passed the first transfer position T1, the developing rotary 23 rotates clockwise by 60 degrees and the photosensitive drum 1
5, color developing units 20Y, 20M, 2
There is no 0C.

4: Formation of Black Image Next, when one point on the outer periphery of the intermediate transfer member 9 (the leading end of the yellow / magenta / cyan image) makes another round and reaches the position shown in FIG. Then, the black toner is developed by the black developing unit 21B, and the black toner image on the photosensitive drum 15 is further transferred onto the intermediate transfer body 9 at the first transfer position T1.

The formation of the latent image and the transfer of the toner to the intermediate transfer member 9 are sequentially performed in the order of yellow, magenta, cyan, and black.
This operation is sequentially performed to form a full-color image including four types of toners of yellow, magenta, cyan, and black on the surface of the intermediate transfer body 9.

Before the transfer of the black toner image to the intermediate transfer member 9 is completed, that is, the image transfer point S of the intermediate transfer member 9 on which the first transfer of the fourth black toner image is completed and the full color image is formed is the second transfer. Before reaching the section T2, the transfer material 2 that has been waiting by the above-described registration roller 8 is started to be conveyed at a proper timing. At the time of forming each color image on the intermediate transfer body 9 for the four times, the transfer roller 10 which waits downward and is not in contact with the intermediate transfer body 9 is simultaneously moved upward by a cam (not shown) to transfer the transfer material 2. At the second transfer portion T2 of the intermediate transfer member 9 and simultaneously applying a bias having a characteristic opposite to that of the toner to the transfer roller 10 to simultaneously transfer four colors of the full-color image on the intermediate transfer member 9 to the transfer material 2 at once. .
The transfer material 2 having passed through the second transfer portion T2 is peeled off from the intermediate transfer member 9 and is conveyed to the fixing portion 25 where the toner is fixed, and then discharged through the discharge rollers 34, 35 and 36 to the upper portion of the electrophotographic image forming apparatus main body 18. The image is discharged onto the unit 37 with the image surface facing downward, and the image forming operation ends.

One of the developing units 20Y, 20M and 20C (the reference numeral is changed to 100) is shown in FIGS. That is, the developing units 20Y, 20M, and 20C have the same configuration. In FIG. 2, the application roller 20YR (the same applies to the application rollers of the developing units 20M and 20C) is omitted. Here, the reference number of the developing roller 20YS (the same applies to the developing rollers of the developing units 20Y, 20M, and 20C) is 102, and the reference number of the developing blade 20YB (the same applies to the developing blades of the developing units 20Y, 20M, and 20C) is 103. Read as follows.

In the developing device 100, the developing frame 101 and the toner frame 107 are welded on the welding surface W (in the present embodiment, ultrasonic welding). Before the toner frame 107 is used, an opening 107a leading to the developing frame 101 is provided with a toner seal 10.
8, the toner seal 108 is opened and the toner in the toner frame 107 is fed into the developing frame 101 in use. In a state where the developing device 100 is mounted on the image forming apparatus main body 18, the developing rotary 2
3, when the developing roller 102 reaches the developing position facing the photosensitive drum 15, the developing roller 102 and the toner feed member 109 are driven from a drive source of the image forming apparatus main body 18 via a shaft coupling and a gear train (not shown). Give rotation to
The developing roller 102 rotates in the direction indicated by the arrow α. Further, the toner feeding member 109 rotates in the direction indicated by the arrow β. As a result, the toner in the toner frame 107 moves into the developing frame 101, the toner is applied to the developing roller 102 by an application roller (not shown), and the layer thickness of the toner on the developing roller 102 is regulated by the developing blade 103. Photoreceptor drum 1
It is sent out to 5.

The developing roller 102 covers the opening 101 a on the front surface of the developing frame 101 so as to cover the developing frame 10.
1 rotatably supported. The space between the developing roller 102 and the developing frame 101 is sealed by a sealing member. As the sealing member, the developing blade 103 and the developing roller 101 cover the opening 101a of the developing frame 101, and
The seal described below is provided.

At both ends of the opening 101a of the developing frame 101, an end peripheral surface sealing member 105 formed of felt or the like for preventing toner from leaking in the lateral direction of the developing roller 102, and a longitudinal portion of the opening 101a of the developing frame 101. A back seal member 106 for filling a gap between the developing blade 103 around the direction and the developing frame 101 is provided. Lower developing roller 1
A sheet member 110 for preventing the developer from blowing out from a gap generated between the lower portion 02 and the lower edge of the opening 101a and the seal member 105 is provided. Sheet member 1
Reference numeral 10 denotes a jaw 1 below the opening 101a of the developing frame 101.
01b, the side of which the leading end faces the developing roller 102 in the short direction is a free end. A part of this free end is in contact with the peripheral surface of the entire developing roller 102 in the longitudinal direction (axial direction of the developing roller).

On the other hand, the longitudinal direction of the sheet member 110 extends to a position where the sheet member 110 overlaps the end peripheral surface sealing member 105, thereby preventing toner from blowing out from the gap.

The end peripheral surface sealing member 105 The lower end 105
a is abutted against the inside of the jaw portion 101b of the developing frame 101, and the upper surface of the lower end 105a of the sealing member 105 is the same as the substantially horizontal surface of the jaw portion 101b, and is in contact with the sheet member 110. In addition, the end peripheral surface sealing member 10
5 is provided on the surface perpendicular to the axial direction of the developing roller 102 in the circumferential direction of the developing roller 102,
2, the developing roller 102 is bent in the middle of the upper right quadrant in FIG.
It reaches the outer edge above the opening 101a of the developing frame 101. Here, when the sheet metal 103a for supporting the developing blade 103 is fixed to the developing frame 101, the sheet metal 10a is fixed.
The upper and lower linear portions of the end peripheral seal member 105 are pressed by 3a.

The back seal member 106 is used for the developing blade 1.
03 is pressed against the developing frame body 101 by the sheet metal 103a to provide a sealing property. The longitudinal edge of the lower end is close to the tip of the developing blade 103 and is in contact with the developing blade 103.

As shown in FIG. 3, the back seal member 106 is a developing blade 103 which is an elastic sheet member except for both ends.
Upper intermediate portion 106a approaching the sheet metal 103a through the
And developing blades 10 at both ends of the upper intermediate portion 106a.
The end 106b is continued in contact with the free beam-shaped portion 3 of FIG.

As shown in FIG. 4A, the back seal member 10
In the single end state, the end portions 106b of 6 have convex portions 106c protruding in the longitudinal direction in a rectangular shape at both end surfaces in the longitudinal direction (the figure shows only one end). In this example, the distal end surface of the convex portion 106c is a plane parallel to the side surface 105b of the end peripheral surface sealing member 105. On the other hand, the side surface 105b of the end peripheral surface sealing member 105 is a surface perpendicular to the longitudinal direction, and the distance L between the opposing side surfaces 105b of the both end peripheral surface sealing members 105 is Convex part 10 of 106b
6c is substantially equal to the distance L1 between both end surfaces 106d perpendicular to the longitudinal direction of the root of 6c.

As shown in FIG. 4A, the developing frame 101
First, the end peripheral surface sealing members 105 are attached to both sides, and when the back sealing member 106 is pushed between the sealing members 105, the convex portion 106c of the back sealing member 106 is crushed, as shown in FIG. become. Here, the portion of the end peripheral surface sealing member 105 that is pressed against the convex portion 106c is also relatively dented, but the material of the seal member 105 and the back seal member 106 is selected so that the convex portion 106c is dominantly crushed. Good. In the state shown in FIG. 4B, the protrusion 106c is pushed toward the back seal member 106, so that one end of the end face 106d is drawn into the back seal member 106 near the corner between the root of the protrusion 106c and the surface 106d. Then, the labyrinth groove 106e is generated.

As a result, the tip area of the convex portion 106c is small, and the convex portion 106c is compressed by the crushing allowance of approximately the height δ, so that the adhesion between the distal end surface of the convex portion 106c and the side surface 105b of the seal member 105 is improved. Is improved. Since the labyrinth groove 106e is produced, the labyrinth effect further enhances the sealing performance, thereby better preventing toner leakage.

It is to be noted that the surface 106d of the back seal member 106 may be provided with an allowance.

(Embodiment 2) Hereinafter, Embodiment 2 will be described with reference to FIGS.

As described above, the developing frame 101 shown in FIG.
An end peripheral seal member 105 for preventing toner leakage in the lateral direction of the developing roller 102 is provided at both ends of the opening 101a, and a developing blade 103 and a developing frame 101 are provided above the opening 101a.
And a back seal member 106 for preventing the toner from blowing out from a gap generated between them.

As shown in FIG. 5A, the back seal member 10
The shape of No. 6 is a direction crossing the side to be sealed by cutting the side surface 105b of the end peripheral sealing member 105 for sealing from the tip of the convex portion 106d (crossing the side surface 105b of the end peripheral sealing member 105). By providing the groove 106d1, the groove 106d1 has a concave shape, and as shown in FIG. 5B, the concave portion is compressed with respect to the end peripheral surface sealing member 105 until the concave portion is substantially linearly deformed, thereby increasing the adhesion. Gives a labyrinth effect, improves sealing performance and prevents toner leakage. That is, a labyrinth groove 106f corresponding to the groove 106d1 is generated in addition to the labyrinth groove 106e in the first embodiment.

Embodiment 3 Hereinafter, Embodiment 3 will be described with reference to FIGS.

As in the above-described embodiments, as shown in FIG. 3, an end peripheral surface sealing member 10 for preventing toner from leaking in the lateral direction of the developing roller 102 is provided at both ends of the opening 101a of the developing frame 101.
5 and the upper portion of the opening 101a, the back seal member 106 for preventing the toner from blowing out from the gap generated between the developing blade 103 and the developing frame 101 is configured to be in contact.

As shown in FIG. 6, the shape of the back seal member 106 is a shape (a) not parallel to the side surface 105b of the peripheral seal member 105 for sealing or a shape (c) having a curved line. Compressing until the inclined portion or the portion having the curved surface which is not parallel to the side surface 105b of the end peripheral sealing member 105 is deformed into a substantially flat surface, thereby increasing the adhesion and having a labyrinth effect, and improving the sealing performance. Prevent toner leakage.

In the shape shown in FIG. 6A, the top surface of the convex portion 106c is inclined with respect to the side surface 105b of the seal member 105. The top 106c4 of this top surface is the end peripheral surface sealing member 1.
05 in a direction crossing the side surface 105b. Therefore, the top portion 106c4 can strongly and closely contact the end peripheral surface sealing member 105 with respect to the side surface 105b. End peripheral surface sealing member 1
When 05 is not made of felt but made of a hard material such as a magnetic seal member, it is effective in improving the adhesion performance. As shown in FIG. 6B, when the convex portion 106c of FIG.
A labyrinth groove 106e is formed in a portion corresponding to the corner of the surface 06d and the surface 106d. In addition, the same effect is obtained even when the top surface of the concave portion 106c is formed into a roof (angle) shape.

The shape of FIG. 6 (c) shows two convex portions 106c2 and 106c
2, and the generatrix of the bumps 106c2 and 106c2 crosses the side surface 105d of the end peripheral seal member 105. When assembled, the bumps 106c2 and 106c2 are crushed as shown in FIG.
A labyrinth groove 106f is formed corresponding to the groove between 106c2, and a labyrinth groove 106e is formed corresponding to the root of the convex portion 106c and the corner of the surface 106d.

In the embodiment, the end of the convex portion provided on the back seal member is a plane parallel to the end peripheral surface seal member, a sloped grooved surface, a two-hump surface, and the like. Without limiting, if you can give a squeeze allowance to the convex part,
The end sealing performance of the back seal member is improved, and the shape of the projection may be a shape other than those described above.

Although the above embodiment has been described with respect to the developing device 100 (specifically, 20Y, 20M, 20C), the same can be applied to the black developing device 21B and the process cartridge 13. That is, the process cartridge 13 is rotatably supported by the cleaning container 14 so that the photosensitive drum 15 covers the opening of the cleaning container 14, and a cleaning blade 16 and a cleaning sheet are provided in a gap between the opening and the photosensitive drum 15. An upper cleaning blade 16 and a squeeze sheet 16a, which are fixed to the cleaning container 14 and cover the gap, are in elastic contact with the peripheral surface of the photosensitive drum 15 over substantially the entire length in the longitudinal direction. Further, the photosensitive drum 15 overlaps the squeeze sheet 16a at both ends of the squeeze sheet 16a.
An end peripheral surface sealing member (not shown) in contact with the peripheral surfaces of both ends of the cleaning blade 16 is provided.
, And a back seal member (not shown) is provided on the back side of the cleaning blade 16.

The process cartridge 1 having the above configuration
Also in 3, the end of the back seal member with respect to the end peripheral surface seal member has the same configuration as the developing device 100.

The process cartridge is a cartridge in which a charging unit, a developing unit or a cleaning unit and an electrophotographic photosensitive drum are integrally formed as a cartridge, and this cartridge is detachably mountable to the main body of the image forming apparatus. . In addition, at least one of the charging unit, the developing unit, and the cleaning unit and the electrophotographic photosensitive drum are integrally formed into a cartridge so that the cartridge can be attached to and detached from the image forming apparatus main body. Further, it refers to a device in which at least the developing means and the electrophotographic photosensitive drum are integrally formed into a cartridge so that the cartridge can be attached to and detached from the image forming apparatus main body.

Although a laser beam printer has been described as an example of an image forming apparatus in the embodiment, the present invention is not limited to this. For example, the present invention is applied to an image forming apparatus such as a copying machine, a facsimile machine, or a word processor. Of course, it is not necessary to limit to the developing device of the process cartridge exemplified in the embodiment. For example, it is also possible to use the developing device of a conventional image forming apparatus that does not use a process cartridge. It is.

[0078]

According to the present invention, when a seal member or a seal member made of a different material that cannot be integrally formed is brought into contact with each other to prevent leakage, the seal member has a convex shape, a concave shape, a shape or a curve that is not parallel to the surface to be sealed. Press one or each seal member of the shape, convex shape, concave shape,
Non-parallel or curved shapes are compressed to increase the adhesiveness and give a labyrinth effect, enhance the sealing performance, and the toner enters the sealing portion of each sealing member, lowers the sealing performance, and passes through the sealing portion. Such toner leakage can be prevented.

[Brief description of the drawings]

 The drawings show embodiments of the present invention.

FIG. 1 is a longitudinal sectional view of an image forming apparatus using a developing device.

FIG. 2 is a longitudinal sectional view of the developing device.

FIG. 3 is a front view of the developing device without a developing roller and a developing blade.

FIGS. 4A and 4B are configuration diagrams of a seal member.

FIGS. 5A and 5B are configuration diagrams of a seal member according to the second embodiment.

FIGS. 6A, 6B, 6C, and 6D are configuration diagrams of a seal member according to the third embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Paper feed cassette 2 ... Transfer material 3 ... Feed roller 4 ... Feed roller 5 ... Retard roller 6 ... Feed guide 7 ... Transport roller 8 ... Registration roller 9 ... Intermediate transfer body 10 ... Transfer roller 11 ... Elastic layer 12 ... Aluminum cylinder 13 ... Process cartridge 14 ... Cleaning container 15 ... Photoconductor drum (electrophotographic photoconductor drum) 16 ... Cleaning blade (cleaning means) 1
6a: Squeeze sheet 17: Charging means 18: Electrophotographic image forming apparatus main body 20: Developing means 20Y: Yellow developing device 20YB ...
Developing blade 20YR Coating roller 20YS Developing roller 20M Magenta developing device 20MS Developing roller 20C Cyan developing device 20CS Developing roller 21 Developing means 21B Black developing device 21BB Developing blade 21BR Coating roller 21BS Developing roller 22 ... Center shaft 23 ... Development rotary 25 ... Fixing unit 26 ... Fixing roller 27 ... Pressing roller 28 ... Heater 29 ... Heater 30 ... Scanner unit 31 ... Polygon mirror 32 ... Imaging lens 33 ... Reflection mirror 34 ... Ejection roller 35 ... Ejection Roller 36: Discharge roller 37: Discharge unit 100: Developing device 101: Developing frame 101a: Opening 101b: Chin 102: Developing roller 103: Developing blade 103a: Sheet metal 105: Edge peripheral surface sealing member 105: Side surface 106: Back seal Material 106a ... upper intermediate portion 106
b ... end part 106c ... convex part 106c1 ... groove 106c
2 ... bump 106c4 ... top 106d ... end face 106
e, 106f labyrinth groove 107 toner container 107a opening 108 toner seal 109 toner feeding member

Claims (15)

[Claims] 1. A developing device which is detachable from an image forming apparatus main body and which uses a toner to develop a latent image formed on an electrophotographic photosensitive drum using a toner. A developing roller supporting the developing roller and forming a toner container; a developing blade fixed to the developing frame and elastically in contact with a peripheral surface in a longitudinal direction of the developing roller; and a developing roller fixed to the developing frame. A sheet member which is in contact with the peripheral surface in the longitudinal direction of the developing roller, an end peripheral surface sealing member which is held by the developing frame and seals both peripheral surfaces at least between the developing blade and the sheet member of the developing roller; A back seal member having an end surface in contact with a side surface of the end peripheral surface seal member; A convex portion protruding in the opposite direction, and in the assembled state, the convex portion is pressed against the end peripheral surface sealing member so as to be crushed and the end peripheral surface seals so that the both end surfaces contact the side surface of the end peripheral sealing member. A developing device, wherein a convex portion of a back seal member in a unitary state protrudes outside the opposite side surface of the member. 2. A labyrinth groove with respect to the side surface of the end peripheral surface sealing member, wherein the convex portion is pressed against the end peripheral surface sealing member and crushed at a corner between the end surface on which the convex portion is provided and the root of the convex portion. The developing device according to claim 1, wherein is formed. 3. A shape of the front end surface of the convex portion has a groove in which a labyrinth groove is formed on a side surface of the end peripheral surface sealing member by being pressed against the end peripheral surface sealing member and crushed. Or the developing device according to 2. 4. The developing device according to claim 1, wherein the end surface of the convex portion at the end of the back seal member in a single body is a plane parallel to the side surface of the end peripheral seal member. 5. The developing device according to claim 1, wherein the front end surface of the convex portion at the end of the back seal member as a single unit has a groove crossing the side surface of the end peripheral seal member. 6. The developing device according to claim 1, wherein the tip of the convex portion at the end of the back seal member in a single body has a linear shape in a direction crossing the side surface of the end peripheral seal member. 7. The developing device according to claim 1, wherein a plurality of bumps in a direction in which a generatrix crosses the side surface of the end peripheral sealing member are arranged in parallel on the end surface of the convex portion at the end of the back sealing member. 8. A process cartridge detachable from an image forming apparatus main body, comprising: an electrophotographic photosensitive drum; and developing means for developing a latent image formed on the electrophotographic photosensitive drum using toner. A developing roller disposed in contact with or at a gap from the electrophotographic photosensitive drum; a developing frame supporting the developing roller and forming a toner container; and a developing roller fixed to the developing frame. A developing blade that elastically contacts the generatrix of the developing roller, a sheet member fixed to the developing frame and in contact with the circumferential surface of the developing roller in the longitudinal direction, and a peripheral surface held at both ends at least between the developing blade and the sheet member of the developing roller. An end peripheral surface sealing member for sealing, and a back seal portion provided on the back surface of the developing blade and having an end surface in contact with a side surface of the end peripheral surface sealing member The back seal member is provided with a convex portion protruding in a longitudinal direction at a part of both end surfaces at an end portion of the single unit, and in an assembled state, the convex portion comes into pressure contact with the end peripheral surface seal member. The convex portion of the back seal member in a unitary state protrudes outside the opposite side surface of the end peripheral seal member so that the both end surfaces are crushed and the both end surfaces contact the side surface of the end peripheral seal member. Process cartridge. 9. A process cartridge detachable from an image forming apparatus main body, comprising: an electrophotographic photosensitive drum; and cleaning means for removing toner remaining after being transferred onto the electrophotographic photosensitive drum. A cleaning member that contacts the electrophotographic photosensitive drum and removes toner remaining on the electrophotographic photosensitive drum after transfer; and a cleaning member that supports the electrophotographic photosensitive drum and removes the toner removed from the electrophotographic photosensitive drum. A cartridge frame forming a toner reservoir to be accommodated, a squeeze sheet fixed to the cartridge frame and elastically contacting the circumferential surface of the electrophotographic photosensitive drum in a longitudinal direction, and a peripheral surface of both ends of the electrophotographic photosensitive drum held by the cartridge frame. An end peripheral surface sealing member for sealing; and an end surface provided on the back of the cleaning member. A back seal member that is in contact with the side surface of the end peripheral surface seal member; The portion is pressed out of contact with the end peripheral surface sealing member and crushed, and the unit is in a state of a single body outside the distance between the opposing side surfaces of the end peripheral surface sealing member such that the both end surfaces contact the side surfaces of the end peripheral sealing member. The process cartridge characterized in that the convex portion of the back seal member protrudes. 10. A labyrinth groove with respect to a side surface of the end peripheral surface sealing member, wherein the convex portion is pressed into contact with the end peripheral surface sealing member and crushed at a corner between the end surface on which the convex portion is provided and the root of the convex portion. The process cartridge according to claim 8, wherein the process cartridge is formed. 11. The end surface of the convex portion has a groove in which a labyrinth groove is formed on the side surface of the end peripheral sealing member by being pressed against the end peripheral sealing member and crushed. Or the process cartridge according to 9 or 10. 12. The process cartridge according to claim 8, wherein a charging unit, a developing unit or a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is detachably mountable to an image forming apparatus main body. 12. The process cartridge according to any one of items 11 to 11. 13. The process cartridge according to claim 8, wherein at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photoreceptor are integrally formed into a cartridge so as to be detachable from an image forming apparatus main body. 12. The process cartridge according to any one of items 11 to 11. 14. The process cartridge according to claim 8, wherein at least the developing means and the electrophotographic photosensitive member are integrally formed into a cartridge and can be attached to and detached from an image forming apparatus main body.
12. The process cartridge according to any one of items 1 to 11. 15. An electrophotographic image forming apparatus having a container for accommodating a toner, and a plurality of sealing members arranged to abut against each other to seal an opening of the container. A process unit that acts on the electrophotographic photosensitive drum; a transfer unit that transfers a toner image formed on the electrophotographic photosensitive drum to a recording medium; an image forming apparatus that transfers the recording medium through a transfer unit and a fixing unit A conveying unit that discharges out of the main body; and the fixing unit. In a portion where the plurality of seal members abut, a convex portion is provided on a part of a surface of the one seal member facing the other seal member. An electrophotograph in which the convex portion is crushed and comes into contact with the other sealing member together with the surface, and a labyrinth groove is formed in a portion corresponding to a corner of the root of the convex portion and the surface. Image forming apparatus.