JPH06317975A - Method for fitting electrifying roller, process cartridge and image forming device and method for assembling process cartridge - Google Patents

Abstract

PURPOSE:To provide a process cartridge capable of electrifying a photosensitive drum by surely keeping an electrifying roller in close contact with it, even if the photosensitive drum shifts in the direction away from the electrifying roller at the time of driving, without adverse effect such as increasing the cost and making the size large. CONSTITUTION:As to a method for fitting the electrifying roller 10 to a frame 14, the electrifying roller 10 is fitted to the frame 14, so that respective allowable range for shifting in the direction orthogonal to the axial line of the electrifying roller 10 on one end side of the photosensitive roller 10 and on the other end side differs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process cartridge using an electrophotographic copying machine, a printer or the like, and an image forming apparatus in which the process cartridge is detachable.

[0002]

2. Description of the Related Art An image forming apparatus such as a printer forms a latent image by selectively exposing a uniformly charged photosensitive drum to form a latent image, and the latent image is visualized with a toner. An image is recorded by transferring the image to a recording medium. In such an apparatus, the toner must be replenished each time it is used up, but this toner replenishment work is not only troublesome, but it may be contaminated. In addition, maintenance of each member can be performed only by a specialized service person, which often causes inconvenience to the user. Therefore, the photosensitive drum, the charger, the developing unit, the cleaning unit, and the like are integrated into an integrated structure to form a cartridge, and the user loads the cartridge into the apparatus main body to replenish the toner or to reach the end of the photosensitive life. Parts that can be replaced, such as body drums, have been put into practical use for easy maintenance. Furthermore, the present inventor has made it easy to collect toner, disassemble, clean, and reassemble it after the toner in the process cartridge is used up, and refill the toner to use again as the process cartridge. The structure of the process cartridge is composed of a lower frame body having a photosensitive drum and process means acting on the drum, and an upper frame body engageable with and separable from the lower frame body and having a toner storing means. I am making a proposal. In the process cartridge, the charging roller, which is a charging unit, is attached to the upper frame so as to be movable in a direction orthogonal to the axial direction of the charging roller. More specifically, the charging roller is rotatably supported by a bearing, and the bearing is attached to a bearing slide guide claw of an upper frame so as to be movable in a direction orthogonal to the axial direction of the charging roller. . At this time, the charging roller is movable in the direction of the photosensitive drum. A spring is arranged on a bearing that rotatably supports the charging roller, and the charging roller biases the charging roller against the photosensitive drum by a predetermined pressing force. When the upper frame body and the lower frame body incorporating the photosensitive drum, the cleaning device and the developing device are assembled, the charging roller is pushed into the drum and moved, and the spring is compressed, and the repulsive force of the spring is exerted. To be in close contact with the photosensitive drum. At this time, a gap is formed between the retaining portion of the bearing slide guide claw and the bearing, and the distance of this gap is the allowable movement amount of the charging roller. Further, a flange gear for receiving a driving force from the drive transmission means of the image forming apparatus main body and rotating the photosensitive drum is fixed to one end of the photosensitive drum.

[0003]

However, in the above-described conventional example, when the process cartridge is driven, the photosensitive drum applies a force in the direction of the pressure angle between the flange gear and the drive gear of the image forming apparatus main body, that is, in the direction away from the charging roller. As a result, the entire drum is displaced in the direction away from the charging roller. At this time, the play of the photosensitive drum on the non-driving side is larger than that on the driving side. To reduce the cost of the process cartridge, the driving side that directly receives the driving force cannot take a large amount of mounting play, but the non-driving side receives much less force than the driving side. This is because it is large and the assemblability is improved. Therefore, the amount of displacement on the non-driving side becomes larger than that on the driving side, and exceeds the movement allowable amount of the charging roller, and as a result, the charging roller and the photosensitive drum are separated from each other, causing charging failure. There was a problem of being lost. As a means to solve this problem,
A method of reducing the amount of displacement of the photoconductor drum during driving by increasing the rigidity of the support portion of the photoconductor drum of the process cartridge can be considered, but this method has the adverse effect of increasing the size of the process cartridge and increasing the cost. Will occur.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to increase the cost and increase the size even if the photosensitive drum is displaced in the direction away from the charging roller when the process cartridge is driven. It is an object of the present invention to provide a process cartridge in which a charging roller can be surely brought into close contact with a photosensitive drum to be charged without causing a harmful effect such as an increase in the charging efficiency.

[0005]

A typical constitution of the present invention for achieving the above object is to provide a charging roller mounting method for mounting a charging roller on a frame, wherein the charging roller is mounted on the frame. It is characterized in that the charging roller is attached such that the allowable movement amount in the direction orthogonal to the axis of the charging roller is different between the one end side and the other end side of the charging roller.

[0006]

In the above structure, even if the photosensitive drum is displaced in the direction away from the charging roller at the time of driving, or if the displacement amount is different between the driving side and the non-driving side, the allowable movement amount of the charging roller. Since they are sufficiently taken by each side, there is no possibility of causing charging failure, and there is no fear of causing adverse effects such as an increase in size of the process cartridge and an increase in cost.

[0007]

【Example】

First Embodiment Next, a process cartridge according to a first embodiment of the present invention and an image forming apparatus using the process cartridge will be specifically described with reference to the drawings.

{Overall Description of Process Cartridge and Image Forming Apparatus Equipped with It} First, the overall configuration of the image forming apparatus will be briefly described. Incidentally, FIG. 1 is a sectional configuration explanatory view of a laser printer equipped with a process cartridge which is one mode of the image forming apparatus, and FIG. 2 is an external perspective view of the laser printer.

This image forming apparatus A is, as shown in FIG.
A process cartridge B having an image carrier and at least one process means is detachably mounted on a cartridge mounting portion 2 inside the apparatus main body 1. An optical system 3 for irradiating an image carrier in the process cartridge B with an optical image based on image information given from an external device or the like is arranged above the inside of the apparatus main body 1, and the apparatus main body is further provided. A cassette 4 for accommodating and accommodating recording media is mounted on the cassette mounting portion 1a at the inner bottom of the unit 1. The recording medium in the cassette 4 is conveyed one by one by the recording medium conveying means 5. Further, the apparatus main body 1 is provided with transfer means 6 for transferring a developer (hereinafter referred to as toner) image formed on the image carrier to a recording medium at a position facing the image carrier of the mounted process cartridge B. A fixing unit 7 for fixing the toner image transferred to the recording medium is provided downstream of the transfer unit 6 in the recording medium conveyance direction. The recording medium on which the toner image is fixed is discharged to the discharging portion 8 located at the upper part of the apparatus by the conveying means 5.

{Image forming apparatus} Next, the image forming apparatus A
The configuration of each part will be described in the order of the optical system 3, the recording medium conveying unit 5, the transfer unit 6, and the fixing unit 7.

(Optical system) The optical system 3 irradiates an optical image on an image carrier based on image information obtained from an external device or the like, and as shown in FIG. 1, a laser diode 3a, a polygon mirror 3b, Scanner motor 3c, imaging lens 3
d is attached as a scanner unit 3e in the apparatus main body 1, and further a reflection mirror 3f is attached in the apparatus main body 1.

When an image signal is given from an external device such as a computer or a word processor, the laser diode 3a emits light according to the image signal and illuminates the polygon mirror 3b as image light. The polygon mirror 3b is rotated at a high speed by the scanner motor 3c, and the image light reflected by the mirror 3b irradiates the image carrier through the imaging lens 3d and the reflection mirror 3f, and the surface of the image carrier is selectively selected. Exposure is performed to form a latent image on the image carrier according to image information.

In the present embodiment, the scanner unit 3e is mounted so as to be inclined obliquely upward so that the light passing through the imaging lens 3d is directed obliquely upward toward the reflection mirror 3f. Further, the scanner unit 3e, which is a means for emitting the laser light, has a closed position (see FIG. 1) that blocks the optical path of the laser light so that the laser light does not inadvertently leak.
There is provided a laser shutter 3g capable of having a middle two-dot chain line position) and an open position (solid line position in FIG. 1) that retreats from the closed position and opens the optical path of the laser light during use.

(Recording medium conveying means) Recording medium conveying means 5
Feeds the recording mediums stacked and accommodated in the cassette 4 one by one to the image forming unit, and also ejects the recording medium through the fixing unit 7
To be transported to. Here, the cassette 4 is provided over substantially the entire bottom surface of the apparatus body 1, and
The cassette mounting portion 1a at the inner bottom is configured so that it can be mounted / removed by grasping and grasping the grip portion 4a from the front side of the apparatus in the direction of arrow a. The cassette 4 has a shaft 4
A stacking plate 4c rotatable about b is biased upward by a spring 4d. When a recording medium is stacked and housed on the stacking plate 4c, the leading end of the recording medium in the feeding direction is locked by the separation claw 4e. To do.

When the cassette 4 is mounted and the feeding is started, the pickup roller 5a is rotated and the recording media in the cassette 4 are separated and fed one by one from the top. The fed recording medium includes a reversing roller 5b, a guide 5c, and a roller 5d.
The sheet is conveyed with the front and back reversed and passed through the first reversal sheet path including the above. Then, the recording medium is conveyed to a pressure nip portion between the image carrier and the transfer roller 6 in the image forming section, and receives the transfer of the toner image formed on the surface of the image carrier. The recording medium to which the toner image has been transferred is guided by the cover guide 5e to reach the fixing unit 7, and the toner image is fixed. Then, the recording medium after passing through the fixing means 7 reaches the bow-shaped second reversal sheet path 5g through the relay conveyance roller 5f. This second reverse sheet path 5
When passing through g, the recording medium is turned upside down again, discharged from the discharge port 8a by the discharge roller pair 5h and 5i, and stacked on the discharge unit 8 provided above the scanner unit 3e and the mounted process cartridge B.

In the apparatus of this embodiment, the conveying path of the recording medium is formed in a so-called "S" shape by the first reversing sheet path and the second conveying sheet path. Therefore, the space of the apparatus can be further reduced, and the recording medium after the image recording can be stacked in the order of pages on the discharge section 8 with the image surface facing downward.

(Transfer Unit) The transfer unit 6 transfers the toner image formed on the image carrier at the image forming section onto the recording medium. As shown in FIG. 1, the transfer means 6 of this embodiment is
The transfer roller 6 is used. That is, the transfer roller 6 is attached to the image carrier of the mounted process cartridge B.
The recording medium is pressed by and the voltage of the opposite polarity to the toner image formed on the image carrier is applied to the transfer roller 6, so that the toner image on the image carrier is transferred to the recording medium.

The transfer roller 6 is pressed against the image carrier by a spring 6b via a bearing 6a. A guide member 6c is provided on the upstream side of the transfer roller 6 for conveying the recording medium to stabilize the entry of the recording medium into the nip portion between the image carrier and the transfer roller 6 and shield the surface of the transfer roller 6. This prevents toner from scattering. Further, the recording medium that has passed through the nip portion between the image carrier and the transfer roller 6 is conveyed so as to be oriented downward by about 20 ° with respect to the horizontal direction, so that transfer separation can be reliably performed.

(Fixing Means) The fixing means 7 is for fixing the toner image transferred onto the recording medium by the voltage application of the transfer roller 6 onto the recording medium. The structure is as shown in FIG. That is, in the fixing means 7, 7a is a heat-resistant film guide member having a substantially semicircular gutter cross section, and a flat plate-shaped ceramic heater 7b having a low heat capacity is disposed along the length in the center of the lower surface of the guide member 7a. I am doing it. Further, the guide member 7a has a cylindrical shape (endless) made of heat-resistant resin.
The thin film 7c is loosely fitted. This film 7c has a thickness of about 50 μm and a polyimide base layer of about 4 μm.
Of the primer layer and a fluorine coating layer of about 10 μm. The base layer is a material with high toughness and is thick enough to withstand various stresses and abrasions applied to the film. The primer layer is made of PTFE + PFA mixed with carbon and has conductivity.

A pressure roller 7d is disposed below the guide member 7a and is constantly pushed up by a spring (not shown) so as to sandwich the film 7c and press it against the ceramic heater 7b. There is. That is, the ceramic heater 7b and the pressure roller 7d form a fixing nip portion with the film 7c interposed therebetween. The pressure roller 7d is made of a core metal and soft silicone rubber, and the outer periphery of the silicone rubber is coated with fluorine.

The ceramic heater 7b is energized to generate heat, and is controlled to a predetermined fixing temperature by the temperature control system of the controller. The pressure roller 7d is rotationally driven in the counterclockwise direction indicated by the arrow in FIG. 1 at a predetermined peripheral speed. By the rotational driving of the pressure roller 7d, the cylindrical film 7c is brought into close contact with the lower surface of the ceramic heater 7b in the fixing nip portion by the rotational frictional force of the roller 7d and slides on the surface of the film guide member 7a. The outer periphery is rotationally driven in the clockwise direction indicated by the arrow in FIG. 1 at a predetermined peripheral speed.

The recording medium that has been transferred to the fixing means 7 after receiving the image transfer is guided by the inlet side guide 7f, and the fixing nip portion between the temperature-controlled ceramic heater 7b and the pressure roller 7d is in a rotationally driven state. It enters between the cylindrical film 7c and the pressure roller 7d, comes into close contact with the lower surface of the ceramic heater 7b through the film 7c, and passes through the fixing nip portion in the overlapping state with the film 7c.

In the process of passing through the fixing nip portion,
The unfixed toner image on the recording medium is heated by the heat of the ceramic heater 7b via the film 7c, and the image is thermally fixed. The recording medium passing through the fixing nip portion is separated from the surface of the rotating film 7c and guided by the outlet side guide 7g to reach the relay conveyance roller 5f, and the discharge roller pair 5h, 5h through the second reversal sheet path 5g. It is discharged onto the discharge portion 8 by 5i.

{Process Cartridge} Next, the structure of each part of the process cartridge B mounted in the image forming apparatus A will be described. 3 is a cross-sectional configuration diagram of the process cartridge, FIG. 4 is an external perspective view of the process cartridge, FIG. 5 is an external perspective view of the process cartridge in an inverted state, and FIG. 6 is a state in which the upper and lower frame bodies are divided. 7 is a cross-sectional explanatory diagram of the process cartridge, FIG. 7 is an internal perspective explanatory diagram on the lower frame side, and FIG. 8 is an internal perspective explanatory diagram on the upper frame side.

The process cartridge B is provided with an image carrier and at least one process means. Here, as the process means, there are, for example, a charging means for charging the surface of the image carrier, a developing means for forming a toner image on the image carrier, a cleaning means for removing the toner remaining on the surface of the image carrier, and the like. As shown in FIGS. 1 and 3, the process cartridge B of the present embodiment has a charging means 10, a developing means 12 containing a toner (developer) contained around an electrophotographic photosensitive drum 9 as an image carrier, and a cleaning. Means 13 are arranged, and these are covered with a housing composed of upper and lower frames 14 and 15 to integrally form a cartridge, which is configured to be attachable to and detachable from the apparatus main body 1.

As shown in FIGS. 6 and 8, the upper frame body 14 is provided with a toner reservoir for the charging means 10, the exposure means 11 and the developing means 12, and the lower frame body 15 is provided with the toner reservoirs. As shown in FIG. 3, the photosensitive drum 9, the developing sleeve of the developing means 12, and the cleaning means 13 are provided. Next, the configuration of each part of the process cartridge B will be described in detail in the order of the photosensitive drum 9, the charging unit 10, the exposing unit 11, the developing unit 12, and the cleaning unit 13.

(Photosensitive Drum) <Construction of Photosensitive Drum> The photosensitive drum 9 according to this embodiment.
As shown in FIG. 9, an organic semiconductor (OPC) 9b is applied as a photosensitive layer on the outer peripheral surface of a cylindrical conductive substrate 9a made of aluminum having a thickness of about 0.8 mm, and a photosensitive drum 9 having an outer diameter of 24 mm is formed. Is configured as. And the drum 9
By transmitting the driving force of a drive motor (not shown) to the flange gear 9c fixed to one end of the photosensitive drum 9
Is configured to rotate according to the image forming operation. The other end of the drum 9 is open. The other end of the open drum 9 is supported by the bearing portion 16a of the bearing member 16 as described later.

<Flange Gear> The flange gear 9c fixed to the left end (driving side) of the photosensitive drum 9 with respect to the recording medium conveyance direction has two gears, and the helical gears on the outside. The gear 9c1 and the spur gear 9c2 are arranged side by side inside. Here, the flange gear 9c is integrally injection molded using a plastic material.

As the material of the flange gear 9c, polyacetal having slidability is used in this embodiment, but other than this, ordinary polyacetal or fluorine-containing polycarbonate may be used.

In the flange gear 9c, the outer helical gear 9c1 and the inner spur gear 9c2 have different diameters. In the present embodiment, the outer helical gear 9c1 has a different diameter.
Is larger in diameter than that of the inner spur gear 9c2. The helical gear 9c1 is wider and has a larger number of teeth than the spur toothed gear 9c2.
Even if the load applied to c is large, the drive force is transmitted from the main body side to rotate the photosensitive drum 9 more reliably, and
A large driving force can be transmitted to the gear that meshes with the gear 9c so that the gear 9c can rotate more reliably.

Each size of the flange gear according to this embodiment is illustrated, but the present invention is not limited to this and can be appropriately selected.

(1) Outer diameter of the helical gear 9c1 (z1) → about 28.9 mm (2) Outer diameter of the spur gear 9c2 (z2) → about 26.1 mm (3) Tooth width of the helical gear 9c1 ( z3) → About 7.7mm (4) Tooth width of spur gear 9c2 (z4) → About 4.3mm (5) Number of teeth of helical gear 9c1 → 33 teeth (6) Number of teeth of spur gear 9c2 → 30 teeth (7) Mod tooth of helical gear 9c1 → 0.8 (8) Mod tooth of helical gear 9c2 → 0.8 (9) Torsion angle and direction of helical gear 9c1 → Right, 14.6 °

Since the flange gear 9c has two gears 9c1 and 9c2 arranged side by side and is a plastic material formed by injection molding, as shown in FIG. 10, the inner side of the bottom of the gear portion is so-called. The meat is removed. for that reason,
The radial strength of the flange gear 9c is weakened, and the flange gear 9c is easily deformed by the load when the driving force is transmitted.

Therefore, in order to prevent this, the reinforcing material 9c4 is press-fitted into the lightening portion 9c3 of the flange gear 9c. It is desirable to press-fit the reinforcing member 9c4 into the lightening portion 9c3 both inside and outside, and according to the experiments conducted by the inventors of the present invention, it was found that the press-fitting condition should be set to about 0 to 50 μm. This is because if the above setting conditions are exceeded, the diameter of the tip of the tooth is increased, and if it is less than that, the effect of increasing the strength is not so great.

In this way, the lightening portion 9 of the flange gear 9c
It has been confirmed by experiments that press-fitting the reinforcing material 9c4 into c3 can eliminate the pitch unevenness that appears on the image at one pitch of the drum gear (flange gear 9c).

Next, regarding the means for fixing the flange gear 9c to the photosensitive drum 9, the groove 9c5 of the flange gear 9c is bent at two portions 9a1 on the end surface of the photosensitive drum 9 with a dedicated tool to perform crimping. The photosensitive drum 9 and the flange gear 9c are joined together. In the present embodiment, there are two caulking points, but the number of caulking points is not limited to this, and it suffices that a fixing force that can withstand the load applied to the flange gear 9c be secured. As a result, a more reliable mechanical fixing means can be achieved by removing the fixing method by adhesion which has been somewhat unstable in the past.

<Drum Grounding Contact> Also, in this embodiment, as shown in FIG. 9, the drum 9 is electrically grounded by bringing the conductive grounding contact 18a into contact with the inner peripheral surface of the photosensitive drum 9. However, the ground contact 18a is provided so as to come into contact with the upper portion of the inner surface of the photosensitive drum 9 at the end opposite to the side where the flange gear 9c is provided.

The ground contact 18a is made of a conductive material such as stainless steel for springs and phosphor bronze for springs.
This is attached to a bearing member 16 that rotatably supports the non-driving side of the photosensitive drum 9. The configuration will be specifically described. As shown in FIG. 11, the base portion 18a1 has a locking hole 18 for press-fitting and locking to a boss provided on the bearing member 16.
a2 is provided, two bases 18a1 are provided with two arms 18a3, and each of the arms 18a3 is provided with a hemispherical projection 18a4 projecting to the rear surface side in FIG. The hemispherical projections 18a4 are provided at different positions on the tips of the arms 18a3.

When the bearing member 16 is attached to the photosensitive drum 9, the ground contact 18a causes the convex portion 18a4 to be pressed against the inner surface of the photosensitive drum 9 by the elastic force of the arm portion 18a3. At this time, since there are a plurality of locations (two locations in this embodiment) that come into contact with the photoconductor drum 9, the reliability of the contact is improved, and the hemispherical convex portion 18a4 is formed at the contact portion. The contact with the photosensitive drum 9 becomes stable.

Further, the ground contact 18a is configured so that only the position of the hemispherical convex portion 18a4 is changed without changing the length of the arm portion 18a3. On the contrary, as shown in FIG. The length of the arm portion 18a3 of the contact 18a may be different. By doing so, the position where the hemispherical convex portion 18a4 contacts the photosensitive drum 9 is displaced in the circumferential direction,
For example, even if the inner surface of the photosensitive drum 9 is damaged in the axial direction, the both hemispherical convex portions 18a4 will not run on the scratched portion at the same time. Therefore, the earth contact becomes more reliable. In the latter case, however, when the length of the arm portion 18a3 is changed, the arm portion 18 when being pressed against the inner surface of the photosensitive drum 9 is changed.
Although the contact pressure of each arm portion 18a3 may be different due to the different deformation amount of a3, this can be easily corrected by changing the bending angle of the arm portion 18a3.

Further, in this embodiment, the ground contact 18a has two arm portions 18a3 as described above.
The arm portion may be formed of three or more, or if the arm portion surely contacts the inner surface of the photoconductor drum 9, the arm portions shown in FIGS.
It is also possible to use one having only one arm portion 18a3 (one which is not divided into two forks) and which does not have the above-mentioned hemispherical convex portion at its tip as shown in FIG.

Here, if the contact pressure of the ground contact 18a against the inner surface of the photosensitive drum 9 is too weak, the hemispherical convex portion 18a4.
Is unable to follow the minute irregularities on the inner surface of the photosensitive drum, and a contact failure is likely to occur, and a sound is generated due to the vibration of the arm portion 18a3. In order to prevent this contact failure and vibration noise, it is necessary to increase the contact pressure, but if it is made too strong, the hemispherical convex portion 18a4 is pressed when the image forming apparatus is used for a long time,
A scratch was generated on the inner surface of the drum, and the hemispherical protrusion 18a4
Vibrations may occur due to the rubbing of the parts, which may cause poor contact or vibrating noise.

Taking these into consideration, the contact pressure of the drum ground contact 18a against the inner surface of the photosensitive drum is about 10 g to 200 g.
It is preferable to set in the range of g. That is, according to an experiment conducted by the inventor of the present invention, if the contact pressure is about 10 g or less, a contact failure is likely to occur due to the rotation of the photosensitive drum 9, and there is a possibility of causing a radio disturbance to other electronic devices. there were. If the contact pressure is about 200 g or more, the inner surface of the photosensitive drum 9 may be scratched at the contact sliding portion with the ground contact 18a when used for a long period of time, resulting in abnormal noise during rotation and poor contact. was there.

The generation of the above-mentioned sound may not be completely removed due to the condition of the inner surface of the photosensitive drum 9 or the like, but conductive grease is applied to the contact sliding portion between the ground contact 18a and the inner surface of the drum. By interposing it, it is possible to more reliably prevent the occurrence of the scratches and the contact failure.

As shown in FIG. 3, the contact position of the ground contact 18a with the inner surface of the photosensitive drum 9 is preferably on the substantially upper side of the inner surface of the drum 9. This is because a force is applied to the photoconductor drum 9 toward the transfer roller 6 side during driving, and this force causes the photoconductor drum 9 to easily move to the transfer roller 6 side by a play amount. Therefore, by arranging the ground contact 18a so as to contact the upper side of the inner surface of the drum, the contact between the two becomes more reliable.

<Drum Support Shaft> As shown in FIG. 9, the photosensitive drum 9 has a drum support shaft 9 whose driving side is made of metal.
The non-driving side is rotatably supported by the bearing portion 16a of the bearing member 16 at d. The drum support shaft 9d
As shown in FIG. 15, is a flange fixedly attached to one end of the photoconductor drum 9 by being press-fitted into the shaft hole portion 15s of the lower frame body 15 in which the photoconductor drum 9 is arranged under a press-fitting condition of 47 μm at maximum. It is inserted into the shaft hole of the gear 9c and rotatably supports the drum 9. By press-fitting the drum support shaft 9d that rotatably supports the photosensitive drum 9 into the shaft hole portion 15s of the lower frame body 15 in this manner, the drum support shaft 9 is attached to the lower frame body 15.
The drum 9 can be supported without screwing d. Therefore, at the time of recycling, the drum support shaft 9
The screw hole for stopping d does not become large and the lower frame 15 cannot be reused, and the backlash of the drum support shaft 9d is reduced to achieve high definition and high image quality.
There is an advantage that the rotation of can be made smoother.

Further, at the end surface of the drum support shaft 9d (the surface exposed to the outside of the process cartridge B), the disassembly work of the press-fitted drum support shaft 9d is facilitated in the disassembling step when recycling the process cartridge B. A screw hole 9d1 for carrying out is provided. In this embodiment, the diameter of the drum support shaft 9d is 6 mm and the diameter of the screw hole 9d3 is 3 mm. The material of the drum support shaft 9d may be metal or plastic. The screw hole 9d1
It is a female screw and is provided in parallel with the mounting direction of the support shaft 9d and substantially at the center of the support shaft 9d.

FIG. 16 shows an example of the work for removing the drum support shaft 9d from the lower frame 15. The extraction tool 19 for extracting the drum support shaft 9d has a screw portion 19a1 at one end and a stopper 19a2 having a diameter of about 10 mm at the other end.
Approximately 40mm in diameter, about 10mm thick on the shaft 19a 19
b. The screw portion 19a1 of the extracting tool 19 is screwed into the screw hole 9d1 of the drum support shaft 9d press-fitted into the lower frame body 15, and the weight 19 is pushed toward the stopper 19a2.
By striking b several times, the drum support shaft 9d can be easily removed from the lower frame body 15. The screw part
19a1 is a male screw, and the screw hole 9d1 as the female screw
Screw together.

In this embodiment, an example in which a screw hole for disassembling work at the time of recycling is provided in the drum support shaft to be press-fitted into the cartridge frame has been described, but the present invention is not limited to this, and the press-fitted parts are extracted. In order to facilitate the above, it is possible to provide the other press-fitted parts.

(Charging Means) <Structure of Charging Means> The charging means is for charging the surface of the photosensitive drum 9, and in this embodiment, it is disclosed in Japanese Patent Laid-Open Publication No. Sho.
A so-called contact charging method as shown in Japanese Patent Laid-Open No. 63-149669 is used. That is, as shown in FIG. 3, the charging roller 10 is rotatably provided on the inner surface of the upper frame 14 via the sliding bearing 10c. This charging roller 10 is provided with an elastic rubber layer such as EPDM or NBR on a metal roller shaft 10b (for example, a conductive core metal such as iron or SUS), and a urethane rubber layer in which carbon is dispersed on the peripheral surface thereof. Or a metal roller shaft 10b covered with a urethane foam rubber layer in which carbon is dispersed.

The charging roller 10 has a sliding bearing 10c rotatably supporting the roller shaft 10b mounted by a bearing slide guide claw 14n of the upper frame 14 so as not to fall off (FIG. 17 (a)). (See FIG. 17), and is attached so as to be slightly slidable toward the photosensitive drum 9 (see FIG. 17B). Further, a sliding bearing 10c rotatably supporting the roller shaft 10b is attached to the photosensitive drum 9 by a spring 10a.
The charging roller 10 is brought into contact with the surface of the photosensitive drum 9 by the urging force.

<Sliding Amount of Charging Roller> As described above, the charging roller 10 is constructed so as to come into contact with the surface of the photosensitive drum 9 and rotate following the rotational drive of the drum 9. When the photoconductor drum 9 is driven by the power transmitted from the drive motor, the drum 9 receives a force toward the transfer roller side. That is, the photosensitive drum 9 is slightly displaced in the direction away from the charging roller 10. More specifically, the amount of displacement on the non-driving side of the photosensitive drum 9 is slightly larger than that on the driving side. As a result, the amount of sliding of the charging roller 10 in the radial direction with respect to the photosensitive drum 9 may not catch up with the amount of displacement of the drum 9, and the photosensitive drum 9 and the charging roller 10 may be separated from each other.

Therefore, in the charging roller 10 according to this embodiment, the sliding amount in the radial direction with respect to the photosensitive drum 9 is set to be larger than that of the conventional one. Further, the charging roller 10 has a different amount of sliding in the radial direction with respect to the photosensitive drum 9 on the left and right in the longitudinal direction. Specifically, the sliding amount of the non-driving side (power feeding side) sliding bearing 10c is It is set to be larger than that on the drive side (non-power supply side). In this embodiment, as shown in FIG.
The sliding amount β of each sliding bearing 10c of the charging roller 10 is
The non-driving side is set to about 1.5 mm and the driving side is set to about 1.0 mm. In this embodiment, the sliding amount β of each of the driving side and non-driving side is set by changing the distance from the center point of the sliding bearing 10c to the receiving surface 10c3, that is, by shortening the distance. ing. That is, when the charging roller 10 is attached to the upper frame 14, the charging roller 10
The charging roller 10 is mounted such that the permissible movement amount in the direction (radial direction) orthogonal to the axis line is different between one end side and the other end side of the charging roller 10.

<Sliding Bearing> The charging roller 10 has a crossing angle with the photosensitive drum 9 to a greater or lesser extent due to a dimensional error of related components including the mounting portion such as the upper frame 14 or the like.
As a result, when the photosensitive drum 9 rotates, the charging roller 10 that rotates in response to the rotation receives a force in the thrust direction and is pushed in one of the thrust directions.
The roller shaft 10b may hit one side wall of the upper frame body 14, and that portion may be scraped off by rubbing. Further, the roller shaft 10b of the charging roller 10 may hit the side wall of the upper frame body 14 due to vibration during distribution of the cartridge, and the portion may be damaged. Then, the roller shaft 10b of the charging roller 10 is caught by the scraped or scratched portion, and the charging roller is damaged.
Image failure may occur due to non-contact between the photosensitive drum 9 and the photosensitive drum 9. Further, when considering the recycling of the product, there is a possibility that the cartridge frame cannot be reused due to the scraping and the scratches.

Therefore, for the purpose of reusing the cartridge frame and facilitating repair of defects in the manufacturing stage, thrust restricting means for restricting the thrust direction force of the charging roller 10 is not provided in the upper frame 14. It is constructed integrally with a sliding bearing 10c that rotatably supports the roller shaft 10b. That is, as shown in FIGS. 18 and 19, each slide bearing 10c is integrally formed with a stopper portion 10c1 bent in a hook shape as the thrust regulating means. In the sliding bearing 10c in this embodiment, the power feeding side (see FIG. 19 (b)) is molded using a conductive resin material containing a large amount of carbon filler, and the non-power feeding side (see FIG. 19 (a)) is polyacetal. It is molded using a non-conductive resin material such as (POM).

In addition, the slide guide claws 14n and the sliding bearing 10c are not damaged when the charging roller 10 receives a force much larger than the thrust direction force during driving due to the drop of the process cartridge or the like. A hanging member 14p hanging from the upper frame 14 is provided outside the sliding bearing 10c in the thrust direction.

When the charging roller 10 is incorporated into the upper frame body 14, first, the bearing slide guide claw 14n of the upper frame body 14 is made to support the sliding bearing 10c via the spring 10a, and then the roller shaft of the charging roller 10 is supported. It is only necessary to fit 10b into the sliding bearing 10c, and by combining the upper frame body 14 with the lower frame body 15, the charging roller 10 is pressed against the photosensitive drum 9 as shown in FIG. Become.

<Voltage Applied to Charging Roller> During image formation, the charging roller 10 is rotated by the rotation of the photosensitive drum 9, and at this time, an oscillating voltage obtained by superposing a DC voltage and an AC voltage on the charging roller 10 is applied. By applying the voltage, the surface of the photosensitive drum 9 is uniformly charged.

The voltage applied to the charging roller 10 will be described in detail. Although the voltage applied to the charging roller 10 may be only the DC voltage, the DC voltage and the AC voltage are superposed as described above for uniform charging. It is preferable to apply the generated oscillating voltage. Preferably, the uniform charging property is improved by applying to the charging roller 10 an oscillating voltage obtained by superimposing an AC voltage and a DC voltage having a peak-to-peak voltage that is at least twice the charging start voltage when only the DC voltage is applied. (JP-A-63-149669, etc.). The oscillating voltage referred to here is a voltage whose voltage value periodically changes with time, and it is preferable that the oscillating voltage has a peak-to-peak voltage that is at least twice the charging start voltage of the surface of the photosensitive drum when only a DC voltage is applied. The waveform is not limited to a sine wave, and may be a rectangular wave, a triangular wave, or a pulse wave, but from the viewpoint of charging sound, a sine wave that does not include harmonic components is preferable. The AC voltage also includes, for example, a rectangular wave voltage formed by periodically turning the DC power supply on and off.

<Power Supply Path to Charging Roller> The power supply path to the charging roller 10 will be described. As shown in FIG. 18, one end 18c1 of the conductive charging bias contact 18c is in pressure contact with the conductive charging bias contact pin on the apparatus main body side, and the other end 18c2 of the charging bias contact 18c is the spring 10a.
Contact with. Further, the sliding bearing 10 in which the spring 10a rotatably supports one end side (power feeding side) of the roller shaft 10b.
It is in contact with c, and power is supplied to the charging roller 10 from the power source on the apparatus main body side through this path.

A sliding bearing on the charging side of the charging roller 10 is provided.
Since 10c is formed of a conductive resin material containing a large amount of carbon filler as described above, it is possible to apply a stable charging bias through the power feeding path.

(Exposure Means) The exposure means 11 is the charging roller.
The surface of the photosensitive drum 9 uniformly charged by 10 is exposed with an optical image from the optical system 3.
As shown in FIG. 3, the upper frame 14 is provided with an opening 11a for irradiating the photosensitive drum 9 with the laser light reflected by the mirror 3f.

(Developing Means) <Structure of Developing Means> The developing means 12 for forming a toner image with the magnetic toner has a toner reservoir 12a for accommodating toner as shown in FIG. Is provided with a toner feeding mechanism 12b for feeding the toner. Further, the toner sent out is rotated in the direction of the arrow in the drawing to a developing sleeve 12d having a roll-shaped magnet 12c having a plurality of magnetic poles inside to form a thin toner layer on the surface thereof. When the toner layer is formed on the developing sleeve 12d, friction between the toner and the developing sleeve 12d and the developing blade 12e provides a triboelectric charge capable of developing the electrostatic latent image on the photosensitive drum 9. A developing blade 12e is attached to the lower frame 15 so as to rub against the surface of the developing sleeve 12d with a constant pressing force in order to regulate the layer thickness of the toner.

<Developing Blade> The developing blade 12e is formed by cutting a flexible material such as polyurethane rubber or silicon rubber into a plate shape and attaching the blade to a supporting member 12e1 such as a sheet metal. The supporting member 12e1 so as to rub against the developing sleeve 12d by the pressing force of
It is accurately positioned and fixed to the mounting surface of 15 with screws 12e2. Further, the developing blade 12e will be changed over time to the supporting member 12e1.
Reinforcing member 12 such as sheet metal to prevent it from peeling off.
The e3 is attached in close contact with the developing blade 12e.

<Toner Feeding Mechanism> As shown in FIG. 3, the magnetic toner feeding mechanism 12b includes a feeding member 12b1 connected to an arm member 12b2 which is swung about a shaft 12b3 as a bottom surface of the toner reservoir 12b1. The toner is sent by reciprocating in the direction of the arrow b along.

The feeding member 12b1, the arm member 12b2 and the shaft
The material 12b3 is made of polypropylene (PP), acrylobutadiene styrene (ABS), high impact polystyrene (HIPS) or the like, and the arm member 12b2 and the shaft 12b3 are integrally molded.

The feed member 12b1 is formed to have a substantially triangular cross-section, and a plurality of long members extending in the direction of the rotation axis of the photosensitive drum 9 are provided so as to scratch the toner on the entire bottom surface of the toner reservoir 12a. It is composed of a rod-shaped member, and several parts of this rod-shaped member are connected to form an integral member.

Arm member 12 integrally formed with the shaft 12b3
b2 are provided at two locations in the longitudinal direction with a certain distance from the side wall of the toner reservoir 12a (see FIG. 20). In this embodiment, b2 is provided with a distance of 15 mm or more from the side wall of the toner reservoir 12a. The toner in the toner reservoir 12a is prevented from being aggregated in a narrow space between the side wall and the arm member 12b2. Further, when the toner is full, the toner resistance applied to the toner feeding member 12b1 and the arm member 12b2 is large,
Although the shaft 12b3 may be twisted due to the resistance force, the twist of the shaft 12b3 is reduced by narrowing the interval between the arm members 12b2.

The shaft 12 serving as the swing center of the arm member 12b2
One end of b3 is connected to a transmission member 17 that is rotatably attached through the side wall of the toner reservoir 12a, and the other end is supported by the bottom of the U-shaped groove 12a1 inside the toner reservoir 12a, and The rib 12 of the lid member 12f covering the upper portion of the toner reservoir 12a
Lifting is prevented by f2, and it is rotatably supported (see Fig. 20). A driving force for transmitting a driving force to the transmission member 17 so as to swing the arm member 12b2 around the shaft 12b3 at a constant angle when the process cartridge B is mounted on the image forming apparatus A. The transmission means is configured to be connected. The driving force transmitting means will be described later.

The feed member 12b1 and the arm member 12b2 are connected to each other so that locking projections 12b4 provided at two positions in the longitudinal direction of the feed member 12b1 are rotatably locked in long holes 12b5 provided in the arm member 12b2. Made by Although not shown, the feed member and the arm member may be integrally made of a resin such as polypropylene and can be bent at the connecting portion.

Therefore, when the arm member 12b2 is swung at a constant angle during image formation, the feeding member 12b1 is in the direction of arrow b along the bottom surface of the toner reservoir 12a as shown by the solid line state and the broken line state in FIG. Move back and forth. As a result, the toner near the bottom of the toner reservoir 12a is fed by the feeding member 12b1 toward the developing sleeve 12d. At this time, since the feeding member 12b1 has a substantially triangular cross-sectional shape, the toner is gently fed along the inclined surface of the feeding member 12b1 by scratching.

Therefore, the magnetic toner in the vicinity of the developing sleeve 12d is less likely to aggregate due to excessive feeding of the toner, and is not insufficient, and the toner layer formed on the surface of the developing sleeve 12d is less likely to deteriorate.

<Lid Member> The toner reservoir 12a has an upper opening covered with a lid member 12f.
f is welded to the opening. As shown in FIG. 3, a hanging member 12f1 is provided on the inner top surface of the lid member 12f,
The distance between the lower end of the hanging member 12f1 and the bottom surface of the toner reservoir is set to be slightly wider than the height of the triangular cross section of the toner feeding member 12b1. Therefore, the toner feeding member 12b1 reciprocates between the toner reservoir bottom surface and the drooping member 12f1. At this time, even if the feeding member 12b1 tries to float from the toner reservoir bottom surface, the drooping member 12
The feeding member 12b1 is prevented from rising by being regulated by f1.

<Driving Force Transmission Means> Next, driving force transmission means for transmitting the driving force to the toner feeding mechanism 12b will be described with reference to FIGS. 20 and 21. 20 shows the AA cross section in FIG. 3, and FIG. 21 shows the BB cross section in FIG.

As shown in FIG. 20, one end of the shaft 12b3, which is the swing center of the toner feeding mechanism 12b, is provided with a toner reservoir of the upper frame body 14.
A transmission member 17, which is rotatably attached through the side wall of 12a, is connected. The transmission member 17 is made of a resin having excellent slidability such as polyacetal (POM) or polyamide, is attached to the upper frame body 14 by a so-called snap fit, and is rotatable about the rotation axis of the shaft 12b3.

On the other hand, the driving force transmitting means, as shown in FIG. 21, meshes the helical gear 9c1 of the flange gear 9c provided at one end of the photosensitive drum 9 with the sleeve gear 12g of the developing sleeve 12d, and then the sleeve gear. 12 g is meshed with the stirring gear 20, and a boss 20a integrally formed with a predetermined distance from the rotation center of the stirring gear 20 is engaged with an elongated hole 17b provided in the arm portion 17a of the transmission member 17. There is.
As a result, the stirring gear 20 rotates in the direction of the arrow in the drawing via the sleeve gear 12g with the rotation of the flange gear 9c that rotates in the direction of the arrow in the drawing, and the transmission member 17 is moved by the boss 20a of the stirring gear 20 in the drawing. Power is transmitted to the shaft 12b3 connected to the transmission member 17 by swinging in the arrow direction, and the toner feeding mechanism 12b is driven.

<Positioning of stirring gear> The stirring gear 20
The rotation axis 20b, which is the center of rotation, is guided by the U-shaped groove 15p1 of the rib 15p formed on the lower frame 15, and the center is determined. Therefore, the precision of meshing with the sleeve gear 12g may be obtained by accurately molding the lower frame body 15. Further, the upper side of the rotating shaft 20b of the stirring gear 20 is regulated by a concave guide 14i provided below the through hole portion of the upper frame body 14 which rotatably supports the transmission member 17. Therefore, the stirring gear 20 is rotatably positioned and supported by combining the upper frame body 14 and the lower frame body 15. With this configuration, it is not necessary to provide a through hole for rotatably supporting the stirring gear 20 in the cartridge frame, and the strength of the cartridge frame can be increased accordingly.

<Developing Sleeve> Next, the developing sleeve 12d on which the toner layer is formed will be described. The developing sleeve 12d and the photosensitive drum 9 have a minute gap (200 μm to 300 μm).
It is positioned so as to face each other. For this reason, in this embodiment, the contact ring portion 12d1 having an outer diameter larger than the outer diameter of the developing sleeve by the above distance is located outside the toner layer forming region in the vicinity of both axial ends of the developing sleeve 12d.
Is provided so that the ring portion 12d1 contacts the outside of the latent image forming area of the photosensitive drum 9.

Here, the photosensitive drum 9 and the developing sleeve 12d
The positional relationship with and will be described. FIG. 22 shows the photosensitive drum 9.
FIG. 23A is a lateral cross-sectional explanatory view showing a positional relationship between the developing sleeve 12d and the developing sleeve 12d and a pressing method of the developing sleeve 12d.
23 is a vertical sectional view showing a section taken along line AA-AA in FIG. 23, and FIG. 23 (b) is a vertical sectional view showing a section taken along line BB-BB in FIG.

As shown in FIG. 22, the developing sleeve 12d on which the toner layer is formed and the photosensitive drum 9 are separated by a very small distance (200
It is positioned so as to face each other. At this time, in the photoconductor drum 9, the shaft hole serving as the rotation center of the flange gear 9c provided at one end of the photoconductor drum 9 has a lower frame body.
It is rotatably supported by the drum support shaft 9d press-fitted into the shaft hole 15s of the shaft 15, and the other end is rotatably supported by the bearing part 16a of the bearing member 16 which is similarly fitted and fixed to the lower frame body 15. The developing sleeve 12d has a contact ring portion 12d1 having an outer diameter larger than the outer diameter by the distance described above and fitted outside the toner layer forming region in the vicinity of both axial end portions of the sleeve 12d. 12d1 contacts the outside of the latent image forming area of the photosensitive drum 9.

The developing sleeve 12d is rotatably supported by sleeve bearings 12h and 12i in the vicinity of both axial ends thereof, and one (non-driving side) sleeve bearing.
12h is outside the toner layer forming area and the contact ring portion 12d1
And the other (driving side) sleeve bearing 12i is located outside the toner layer forming region and outside the contact ring portion 12d1. The sleeve bearings 12h and 12i are attached to the lower frame body 15 so as to be slidable in the direction of the arrow in FIG. 22, and further, a protrusion extending rearward thereof is provided with a pressing spring 12j. The developing sleeve 12d is pushed by the wall of the body 15 and always urges the developing sleeve 12d toward the photosensitive drum 9. As a result, the contact ring 12d1 is moved to the photosensitive drum 9
, The distance between the developing sleeve 12d and the photosensitive drum 9 is always guaranteed, and the flange gear 9 of the photosensitive drum 9 is always secured.
The driving force can be transmitted to the sleeve gear 12g of the developing sleeve 12d that meshes with c and the helical gear 9c1 of the gear 9c.

<Sliding Amount of Developing Sleeve> The slidable direction of the sleeve bearings 12h and 12i described above will be described with reference to FIG. First, the developing sleeve 12d
Speaking from the driving side, when the driving force is transmitted from the driving motor of the apparatus main body to the helical gear 9c1 of the flange gear 9c, the driving force is transmitted from the helical gear 9c1 to the sleeve gear 12g. The meshing force is directed in a direction inclined by a pressure angle (20 ° in this embodiment) from the tangential direction between the meshing pitch circle of the helical gear 9c1 and the meshing pitch circle of the sleeve gear 12g. Therefore, the meshing force is directed in the direction of arrow P (θ≈20 °) shown in FIG. At this time, when the sleeve bearing 12h is slid in a direction parallel to the straight line connecting the rotation center of the photosensitive drum 9 and the rotation center of the developing sleeve 12d, the meshing force P is slid with the component force Ps in the sliding direction and the horizontal direction. When it is decomposed into the component force Ph in the vertical direction and the component force Ps in the vertical direction, the component force Ps in the sliding direction and the horizontal direction is directed in the direction away from the photosensitive drum 9, as shown in FIG. Therefore, on the driving side of the developing sleeve 12d, the distance between the photosensitive drum 9 and the developing sleeve 12d is likely to change due to the meshing force between the helical gear 9c1 of the flange gear 9c and the sleeve gear 12g, and the developing sleeve 12d on the developing sleeve 12d. The toner may not accurately move to the photosensitive drum 9, which may cause deterioration of developability.

Therefore, in this embodiment, the flange gear 9c
Taking into account the transmission of the driving force from the helical gear 9c1 to the sleeve gear 12g, as shown in FIG.
The slidable direction of the sleeve bearing 12i on the driving side of d (the side on which the sleeve gear 12g is attached) is set to the arrow Q direction. That is, the engagement force P between the helical gear 9c1 of the flange gear 9c and the sleeve gear 12g and the drive side sleeve bearing
The angle ψ with the slidable direction of 12i (arrow Q direction) is
The value is set to a value slightly larger than 90 ° (about 92 ° in this embodiment). With this configuration, the component force Ps of the meshing force P in the sliding direction and the horizontal direction is almost eliminated, and in the present embodiment, the component force Ps slightly applies the developing sleeve 12d to the photosensitive drum 9 side. Acts in the direction. In such a case, the developing sleeve 12d is pressed by the spring pressure α of the pressing spring 12j so that the photosensitive drum 9 and the developing sleeve 12d
The distance from d is kept constant, and accurate development can be performed.

Next, the sliding direction of the sleeve bearing 12h on the non-driving side of the developing sleeve 12d (the side on which the sleeve gear 12g is not attached) will be described. On the non-driving side, unlike the driving side described above, no force is received from the other, so that the sliding direction of the sleeve bearing 12h is as shown in FIG. 23 (b), the center of the photosensitive drum 9 and the developing sleeve 12d.
Keep it substantially horizontal to the line connecting the centers of.

As described above, when the developing sleeve 12d is independently pressed against the photosensitive drum 9, the developing sleeve 12d and the photosensitive drum 9 are changed by changing the pressing angle of the developing sleeve 12d between the driving side and the non-driving side. Since the positional relationship between and is always maintained properly, accurate development can be performed.

The slidable direction of the sleeve bearing 12i on the driving side may be set to be substantially parallel to the straight line connecting the center of the photosensitive drum 9 and the center of the developing sleeve 12d as in the non-driving side. That is, as described above, on the driving side, the component force Ps of the meshing force P between the flange gear 9c and the sleeve gear 12g in the sliding direction of the sleeve bearing 12i causes a force to act in the direction in which the developing sleeve 12d separates from the photosensitive drum 9. Therefore, in this embodiment, the driving side pressing spring is arranged so that the developing sleeve 12d can be pressed against the component force Ps.
It is sufficient to set the pressure applied by 12j larger than the non-driving side by the component force Ps. That is, when the pressure applied to the developing sleeve 12d by the non-driving side pressing spring 12j is P ₁ ,
The pressing force P ₂ of the driving side pressing spring 12j is P ₂
= P ₁ + Ps, the developing sleeve 12d is always subjected to an appropriate pressing force to ensure a constant distance from the photosensitive drum 9.

<Sleeve Bearing Retaining Protrusion> A retaining protrusion 12i1 is provided above the drive-side sleeve bearing 12i of the developing sleeve 12d, and when the developing sleeve 12d is assembled during assembly work, Pressing spring 12j
This prevents the developing sleeve 12d from protruding. As described above, the retaining projection 12i1 is different in the pressing direction of the pressing spring 12j from the sliding direction of the sleeve bearing 12i.
The force of 12j causes a rotational moment in the clockwise direction in FIG. 23, and is provided on the upper portion of the sleeve bearing 12i to receive the force.

<Strength of Frame of Developing-side Driving Unit> When the driving force is transmitted to the sleeve gear 12g, the sleeve gear
A downward force (direction of arrow P in FIG. 23 (a)) is applied to 12g, and the lower frame body 15 directly receives the force via the sleeve bearing 12i, and the drive side portion of the lower frame body 15 is bent. There is a risk that Therefore, this embodiment has the following configuration.

First, the drum support shaft 9 of the photosensitive drum 9
The side wall supporting d and the side wall supporting the driving side of the developing sleeve 12d are integrally connected as shown in FIG.
The force applied to the drive portion of the lower frame body 15 is dispersed by molding the drive side portion (the right end portion in FIG. 7) of FIG. Secondly, a large number of ribs 15p are provided on the bottom surface (the surface to which the downward force is applied as described above) formed in a substantially box shape so as to increase the strength of that portion. Thirdly, as shown in FIG. 22, by making the sleeve bearing 12i closer to the side wall of the lower frame body 15 than the other sleeve bearing 12h, the above-mentioned downward force is applied.
The influence exerted on the lower frame 15 via 12i is reduced.

By constructing as described above, the lower frame body
It is possible to increase the strength of the drive-side portion of the frame 15, particularly the frame body corresponding to the drive-side portion of the developing means 12. Although all of the above three methods are used in this embodiment, it goes without saying that each of these methods alone can be effective.

<Coupling of sleeve gear and developing sleeve>
Next, a method of connecting the sleeve gear 12g and the developing sleeve 12d will be described. FIG. 25 is an explanatory view showing a fitted state of the developing sleeve 12d and the sleeve gear 12g. Figure 25
(A) A cylindrical developing sleeve having an outer diameter of 12 mm
A sleeve flange 12k is fitted to one end side (driving side) of 12d and is fixed by adhesion, caulking, press fitting, or the like. The sleeve flange 12k is rotatably supported by a stepped portion 12k1 having an outer diameter smaller than the inner diameter of the gate portion 12d2 of the abutment ring portion 12d1 and a sleeve bearing 12i.
There is provided a step portion 12k2 having an outer diameter smaller than the outer diameter, and a fitting portion 12k3 having an uneven portion that fits with the sleeve gear 12g.

Since the protruding length of the step portion 12k1 of the sleeve flange 12k is larger than the thickness of the gate portion 12d2 of the contact ring portion 12d1, even if the developing sleeve 12d moves in the thrust direction, the sleeve bearing 12i Does not rub against the contact ring portion 12d1. The step portion 12k2 of the sleeve flange 12k is rotatably supported by the sleeve bearing 12i, and the fitting diameter is about 6 mm to 8 mm.

Further, as shown in FIG. 25 (b), the fitting portion 12k3 of the sleeve flange 12k fitted with the sleeve gear 12g is formed with two convex portions 12k4 and concave portions 12k5 on the cylinder. The outer diameter of the stepped portion 12k2 is one step thinner. The diameter d of the concave portion 12k5 is approximately φ4 mm to 5 mm, and the convex portion 12k4 has a height of approximately 0.7 mm and a width of approximately 2.0 mm.
The outer diameter D is concentric with the outer diameter d of the recess 12k5. In the recess 12k5 of the fitting portion 12k3, the sleeve flange 12k and the sleeve gear 12g are statically fitted (H-js fitting in the case of the hole axis), centered, and backlash removed. Therefore, the convex portion 12k4 of the fitting portion 12k3 has play. Further, the sleeve gear 12g has a fitting hole 12 for fitting with the fitting portion 12k3 of the sleeve flange 12k.
The g2 is provided, and the boss portion 12g1 is further provided to make the fitting portion of the sleeve flange 12k with the fitting portion 12k3 longer than the tooth width to improve the allowable transmission force.

The sleeve flange 12k can be made of aluminum alloy, plastic such as polyacetal (POM), polybutylene terephthalate (PBT) or polyamide (PA). Also, the sleeve gear
As the material of 12 g, plastics such as polyacetal (POM), polybutylene terephthalate (PBT), polyamide (PA), and fluorine-containing polycarbonate (PC) can be used.

In this embodiment, the concave and convex portions of the fitting portion 12k3 of the sleeve flange 12k that fits with the sleeve gear 12g are provided at two locations, but the same effect can be obtained at three or four locations. In particular, when the sleeve gear 12g is manufactured by injection molding of plastic, the four recessed portions have a more uniform wall thickness, which makes it easier to obtain accuracy. Also, the sleeve flange 12k and the sleeve gear 12g are fitted parts.
In the 12k3 recessed portion 12k5, a static fit was used.
K4 may be a statically fitted fit, and the recess 12k5 may be provided with play.

(Cleaning Means) <Structure of Cleaning Means> Next, the cleaning means 13
Is for removing the toner remaining on the photosensitive drum 9 after the toner image on the photosensitive drum 9 is transferred onto the recording medium by the transfer means 6. This cleaning means
As shown in FIG. 3, reference numeral 13 denotes a cleaning blade 13a for contacting the surface of the photosensitive drum 9 and scraping off the toner remaining on the drum 9, and a blade 13a for scooping the scraped off toner. The squi sheet 13b located below and in contact with the surface of the photosensitive drum 9
And a waste toner reservoir for storing the waste toner that has been scooped
It is composed of 13c and.

<Squi sheet> Here, the above-mentioned Squi sheet
A method of attaching 13b will be described. This sheet 13b
Is attached to the mounting surface 13d of the waste toner reservoir 13c with a double-sided tape. At this time, the waste toner reservoir 13c is composed of a lower frame body 15 and an upper frame body 14, is made of a resin material, and has some irregularities and small deformations. Therefore, as shown in FIG. 26, if the double-faced tape 13e is simply attached to the mounting surface 13d and the squeeze sheet 13b is attached to this tape 13e, the undulation U is caused at the tip of the sheet 13b (the contact portion with the photosensitive drum 9). May occur. In this way, the squishy sheet 13b
If there is an undulation U at the tip of the sheet, the sheet 13b does not adhere to the surface of the photoconductor drum 9, and the toner scraped off by the cleaning blade 13e cannot be reliably scooped.

Therefore, when attaching the squi sheet 13b, as shown in FIG. 27 (a), the attachment surface 13d at the lower part of the toner reservoir is pulled downward by the pulling tool 21 to be curved by elastic deformation, and the squi sheet 13b is attached in this state. By releasing the curvature after attaching, the squi sheet 13b
It is conceivable to apply tension to the tip of the to prevent the undulation.

However, in the process cartridge B, which has been downsized in recent years, the squeeze sheet 13
Since the dimension of the mounting surface 13d of b is also small, the mounting surface 13d
If you attach the squisheet 13b in a curved state,
As shown in FIG. 27 (a), both sides of the lower end of the squishy sheet 13b
13b1 protrudes from the mounting surface 13d and projects downward. If the squi sheet 13b projects below the mounting surface 13d, the recording medium may be caught by the squi sheet 13b that projects, as is clear from the sectional view of FIG.

When the squeeze sheet 13b is attached with the mounting surface 13d being curved, the double-faced tape 13e will stick out from under the squeeze sheet 13b as shown in FIG. 27 (b). Therefore, in this state, as shown in FIG. 27 (b), the squeeze sheet 13 b is attached to the double-faced tape 13 e with the application tool 22.
When it is pressed against, the protruding tape 13e sticks to the sticking tool 22, and as shown in FIG. 27 (c), the sticking tool 22
The double-sided tape 13e may be peeled off from the mounting surface 13d when the squi sheet 13b is removed, which may result in defective mounting of the squi sheet 13b.

Therefore, in the present embodiment, the lower end shape of the squeeze sheet 13b is made substantially the same as the shape in which the attachment surface 13d is pulled and curved by the tension tool 21 as shown in FIG. 28 (a). That is, the sheet width is formed such that the central portion in the sheet longitudinal direction is wider than both end portions.
This prevents the curved double-sided tape 13e from protruding from the squi sheet 13b when the squi sheet 13b is attached. Also, remove the tension with the tension tool 21,
As shown in FIG. 28 (b), when the curved surface of the mounting surface 13d is released and tension is applied to the upper end of the squi sheet 13b, the lower end of the seat does not project downward from the mounting surface 13d. Therefore, the squishy sheet as described above
It is possible to prevent the recording medium from being caught by 13b and the mounting failure of the squi sheet 13d.

In consideration of simplification of processing of the squi sheet 13b and the life of the processing tool, it is desirable that the lower end shape of the squi sheet 13b be linear. For this reason
As shown by 29, the lower end of the seat may be linearly configured so that the central portion in the seat longitudinal direction is wider than both end portions in accordance with the amount of curvature of the mounting surface 13d.

Further, in the present embodiment, the mounting surface of the squishy sheet is
When bending 13d, it was pulled by the pulling tool 21, but as shown in FIG.
It goes without saying that the squeeze sheet mounting surface 13d may be curved by pressing the upper part of the partition plate 13c1 in the waste toner reservoir 13c integrated with 13d by the pressing tool 23.

Further, in the present embodiment, the squeegee sheet mounting surface 13d is formed below the waste toner reservoir 13c, but the squeegee sheet 13b is attached to a mounting surface such as a metal plate which is a member different from the waste toner reservoir 13c, and this metal plate is attached. The same effect can be obtained with a configuration in which the waste toner reservoir 13c is incorporated.

<Cleaning Blade> As shown in FIG. 3, the cleaning blade 13a is made of an elastic member such as polyurethane rubber (JIS A hardness of 60 to 75 degrees) and is attached to a supporting member 13a1 which is a sheet metal such as a cold rolled steel plate. It is fixed integrally. The fixed support member 13a1 of the cleaning blade 13a is attached to the cleaning blade attachment seat surface of the lower frame 15 to which the photosensitive drum 9 is attached by screws or the like. Incidentally, the cleaning blade mounting seat surface of the lower frame body 15 is formed by the blade when the supporting member 13a1 fixed to the blade 13a is mounted.
The edge portion 13a is accurately molded so as to be pressed against the photosensitive drum 9 with a predetermined contact pressure.

Since the primary charging bias, which is a voltage obtained by superimposing the DC voltage and the AC voltage, is applied to the charging roller 10 in the process cartridge B as described above, the AC component (about 2 kV _pp ) is applied to the photosensitive roller. The body drum 9 vibrates slightly. The minute vibration of the photosensitive drum 9 may trigger the cleaning blade 13a pressed against the drum 9 to cause so-called stick slip and generate vibration. The vibration of the cleaning blade 13a due to this stick slip is large, and the vibration is caused by the blade 13a.
Noise may be generated by being transmitted to the lower frame body 15 and further to the upper frame body 14 through the supporting member 13a1 fixed to a1.

Therefore, in this embodiment, as a means for suppressing the noise caused by the vibration of the cleaning blade 13a, a rib 14j is provided at a predetermined position inside the upper frame 14 as shown in FIGS. Abuts against the upper surface of the fixed support member 13a1. Further, a sealing member S made of foamed polyurethane or the like is provided on the rib 14j in order to prevent the waste toner from leaking from the waste toner reservoir 13c.
₁ is attached to the rib 14j and the support member.
Crushed between 13a1. Therefore, the upper frame 14
By the repulsive force of the rib 14j and the seal member S ₁ , the vibration of the cleaning blade 13a can be suppressed, and the generation of noise due to the vibration can be prevented. Supporting member 13a1 of the thus cleaning blade 13a, the sealing member S ₁
It is sandwiched between the upper frame body 14 and the lower frame body 15 via the. That is, the support member 13a1 is screwed to the lower frame body 15 to attach the cleaning blade 13a, and thereafter,
The process cartridge B is assembled by locking the upper and lower frames 14 and 15 so as to press the support member 13a1 with the upper frame 14.

The rib 14j is set so that its height, that is, the gap between the upper surface of the support member 13a1 against which the rib 14j abuts and the inner surface of the upper frame 14 is "zero". Further, in this embodiment, the length L _R of the rib 14j of the upper frame 14 in the longitudinal direction is
However, at the center of the cleaning blade 13a in the longitudinal direction,
It is set to be 80 mm or more. Therefore, the upper frame body 14 is moved about by the reaction force from the cleaning blade 13a.
Although it bends by about 0.5 mm to 1.0 mm, it may be formed in advance to allow for the bending.

<Relationship Between Toner Average Particle Size and Blade Contact Pressure> Further, in recent years, further improvement in image quality has been desired, and the toner particle size is being reduced. Conventionally, a toner having an average particle size of about 9 μm was used, but in this embodiment, the average particle size is 7 μm.
A toner of about μm is used, and the normal distribution chart of the toner is shown in FIG. As can be seen from FIG. 33, the smaller the particle size of the toner, the larger the amount of fine particles.
Therefore, unless the contact pressure of the cleaning blade 13a with respect to the photosensitive drum 9 is increased in accordance with the reduction in the particle size of the toner, the toner may slip through the cleaning blade 13a, which may cause so-called cleaning failure. . Further, the toner that has slipped through adheres to the surface of the photosensitive drum 9 and is crushed by the charging roller 10 and fused to the surface of the drum, or adheres to the charging roller 10 and causes charging failure. There is a risk.

Therefore, in this embodiment, the contact pressure of the cleaning blade 13a with respect to the photosensitive drum 9 is increased in accordance with the reduction in the particle size of the toner. Hereinafter, the method of measuring the contact pressure of the cleaning blade 13a, and the applicant of the present invention, by changing the blade contact pressure and the toner particle size, the cleaning property and charging property, and the state of the photoconductor drum 5000 in a normal environment The experiment results of the endurance experiment will be described.

First, the penetration amount λ and the set angle ψ of the blade 13a with respect to the photosensitive drum 9 will be described with reference to FIG. The blade penetration amount λ is a virtual amount in which the tip of the blade 13a enters the photoconductor drum 9 without being deformed, and the blade setting angle ψ is a point where the tip of the blade 13a and the photoconductor drum 9 intersect. Tangent and blade
It is an angle with 13a.

Based on the above, the method for measuring the blade contact pressure will be described with reference to FIG. First, in order to measure the linear pressure per unit cm, a blade 13a cut into a width of 1 cm is set on a blade base 57 movable by a motor 56 in the direction of the arrow in the figure, and the blade 13a is set at about 20 ° to 25 °.
Of these, a desired set angle ψ is set and the load sensor 58 is contacted. Next, the blade base 57 is moved toward the load sensor by the desired penetration amount λ, the detected value of the load sensor 58 at that time is amplified by the amplifier 59, and is read by the voltmeter 60. Then, the load per unit voltage obtained in advance is the unit cm
It is measured by replacing the linear pressure per hit.
The value thus measured is used as the blade contact pressure.

The applicant of the present invention changes the blade contact pressure and the toner particle size by using the above blade contact pressure measuring method to measure the cleaning property, the charging property, and the state of the photosensitive drum of 5000 sheets in a normal environment. After conducting an endurance experiment,
The results shown in FIG. 36 were obtained. In order to stabilize the charging property, the charging roller has a DC voltage of about 1 kV and a charging voltage of about 2 kV.
A certain AC voltage is superimposed. The developing method is a case where reversal development is performed using a one-component magnetic toner. Here, the reversal development is a development using a toner having a charging polarity which is the same as the latent image potential. In this embodiment, a negative latent image potential is formed on the surface of the image bearing member by the contact charging means to which a negative charge is applied, and the development is performed with the same negatively charged toner. Furthermore, the process speed is about 20 mm
/ Sec to 160 mm / sec.

Referring to FIG. 36, Test No. 1 is a conventional combination, and as a result of an experiment conducted using a toner having a blade contact pressure of 15 gf / cm and an average particle size of 9 μm, it is natural that Since the cleaning property was obtained, the charging property and the state of the photosensitive drum were also good.

For the test No. 2, the blade contact pressure 15
When an experiment was conducted using a toner having an average particle size of 7 μm at gf / cm, cleaning failure occurred from about 1000 sheets,
Along with that, charging defects began to occur from several hundreds of sheets. Further, the toner passing through the blade 13a is crushed by the vibration of the charging roller 10 due to the superimposed voltage and crushed onto the drum surface to cause toner fusion.

For test No. 3, set the blade contact pressure to
When an experiment was conducted using a toner having an average particle size of 7 μm increased to 20 gf / cm, the toner that had slipped through was less, but the cleaning property was still insufficient. The accumulated toner is accumulated on the contact surface side of the sheet, and when the apparatus is activated after 2000 sheets, the accumulated toner is taken to the photoconductor drum 9 by the deformation of the blade tip, and the toner adheres to the charging roller 10 to cause charging failure. I got it. However, by continuously recording a few sheets, the toner adhering to the charging roller 10 was gradually removed, and the charging returned to normal.

For test No. 4, set the blade contact pressure to
When an experiment was conducted using a toner having an average particle size of 4 μm while maintaining 20 gf / cm, the result substantially the same as the test No. 3 was obtained.

For test No. 5, set the blade contact pressure to
An experiment was conducted using a toner having an average particle size of 7 μm increased to 25 gf / cm. As a result, the toner slipped through almost completely, and therefore the toner adhering to the contact surface side of the blade 13a with the drum 9 also almost disappeared. In the durability test of 5000 sheets, the toner did not slip through at the time of starting the apparatus and the normal cleaning failure disappeared, the cleaning property and the charging property were good, and the state of the photosensitive drum was also good.

With respect to Test No. 6 and Test No. 7, an experiment was conducted using a toner having an average particle size of 5 μm and an average particle size of 4 μm with the blade contact pressure kept at 25 gf / cm.
Similar to the result of Test No. 5, the cleaning property and the charging property were good, and the state of the photosensitive drum was also good.

In Test No. 8 and Test No. 10, the upper limit of the blade contact pressure when using toner having an average particle size of 7 μm was measured, and the contact pressure was 60 gf /
When the contact pressure was 65 gf / cm, a considerable number of scratches were formed on the drum surface, and streaks due to the scratches were generated on the image after about 4000 sheets.

Further, in the test No. 9 and the test No. 11, the upper limit of the blade contact pressure when the toner having the average particle diameter of 4 μm is used is measured.
And the same as the test No. 10 result, blade contact pressure 60gf /
In cm, there was no problem on the image, but blade contact pressure 65gf /
In cm, a lot of scratches were made on the drum surface, and streaks due to the scratches were generated on the image after about 4000 sheets.

Therefore, when using a toner having an average particle size of 7 μm or less, the blade contact pressure must be set to at least 20 gf / cm or more, in order to prevent defective cleaning more completely and always obtain a good image. It is desirable to set the blade contact pressure within the range of 25 gf / cm or more and 60 gf / cm or less, and considering the upper and lower limits, it is desirable to set the blade contact pressure to about 36 gf / cm. . As described above, according to this embodiment, the elastic cleaning blade 13 is used when the average particle diameter of the toner is 4 μm to 7 μm.
A was attached to the lower frame 15 so as to contact the photosensitive drum 9 with a contact pressure of 25 gf / cm or more and 60 gf / cm or less.

(Upper and Lower Frame) Next, the process cartridge B
The upper and lower frame bodies 14 and 15 that form the housing of FIG. As shown in FIG. 6, on the lower frame 15 side, in addition to the photosensitive drum 9, a developing sleeve 12d constituting the developing means 12, a developing blade 12e, and further a cleaning means 13 are provided.
On the other hand, as shown in FIG. 6, the charging roller 1 is provided on the upper frame 14 side.
0, a toner reservoir 12a and a toner feeding mechanism 12b constituting the developing means 12 are provided.

In order to connect the upper and lower frame members 14 and 15, the upper frame member 14 is provided with four pairs of locking claws 14a in the longitudinal direction at substantially equal intervals as shown in FIGS. 8 and 38. As shown in FIGS. 7 and 37, the lower frame 15 is integrally formed with the body 14 and has a locking opening 15a and a locking projection 15b for locking the locking claw 14a. It is integrally molded with 15. Therefore, the upper and lower frame bodies 14 and 15 are forcibly fitted and the locking claw 14a is locked into the locking opening 15.
The upper and lower frame bodies 14 and 15 are joined by being locked to a and the locking projection 15b. Here, since the locking claw 14a and the locking opening 15a are elastically locked, they can be removed. In order to make this connection state more reliable, locking claws 15c and locking openings 15d are provided in the vicinity of both longitudinal ends of the lower frame body 15 as shown in FIGS. 7 and 37. As shown in FIGS. 8 and 38, the locking claws 15c and the locking openings are provided near both ends in the longitudinal direction of 14 as shown in FIGS.
A locking opening 14b and a locking claw 14c for locking 15d are provided. Further, as shown in FIGS. 7 and 37, positioning protrusions 15m are formed in the vicinity of both longitudinal ends of the lower frame 15 to which the photosensitive drum 9 is attached.
When the upper frame 14 is connected as shown in FIG. 4, 15 m penetrates through the through hole 14 g formed in the upper frame 14 and projects upward.

When the members constituting the process cartridge B are divided into the upper and lower frames 14 and 15 as described above, it is necessary to position them with respect to the photosensitive drum 9, for example, the developing sleeve 12d and the developing blade. By providing the 12e, the cleaning blade 13a, and the like on the same frame body (the lower frame body 15 in this embodiment), each member can be accurately positioned and the process cartridge B can be easily assembled. it can.

Further, the lower frame member 15 of this embodiment has a structure shown in FIG.
As shown in 37, a fitting recess 15n is provided near one end of the frame body.
Is provided. Further, as shown in FIGS. 8 and 38, the upper frame 14 has a fitting recess near the one end of the frame at a substantially intermediate position between the locking claws 14a and near the locking claw 14a. A fitting convex portion 14h that fits into 15n is provided.

Further, in the lower frame body 15 of this embodiment, as shown in FIG.
As shown in 37, a pair of fitting concave portions 15e, fitting convex portions 15f1, and fitting concave portions 15f2 are provided near the four corners of the frame body, respectively. Further, as shown in FIGS. 8 and 38, the upper frame 14 is provided with the fitting recess 15e and the fitting projection 15f1 near the four corners of the frame.
A pair of fitting protrusions 14d, a fitting recess 14e1 and a fitting protrusion 14e2 are provided for fitting the fitting recess 15f2.
Further, a locking opening 15f3 is provided in the vicinity of the fitting recess 15f2, and a locking claw 14e3 that is locked in the locking opening 15f3 is provided in the vicinity of the fitting projection 14e2.

Therefore, when the upper and lower frame bodies 14 and 15 are joined together, the fitting projections 14h, 14d and 14e provided on the upper and lower frame bodies 14 and 15 are joined.
Fit 2 and 15f1 into the fitting recesses 15n, 15e, 15f2 and 14e1,
Furthermore, by locking the locking claw 14e3 to the locking opening 15f3,
The connection between the two frame bodies 14 and 15 is strong, and even if a twisting force is applied to the upper and lower frame bodies 14 and 15 in the connected state, the connected state does not shift.

The positions of the fitting convex portion and the fitting concave portion and the positions of the locking claw and the locking opening are not limited to those described above, and the upper and lower frame members 14 and
It may be provided at another position as long as it can be prevented from being displaced with respect to the twisting force with respect to 15.

Further, as shown in FIG. 6, the upper frame 14 has a shutter mechanism 24 for protecting the photosensitive drum 9 from outside light and dust when the process cartridge B is removed from the image forming apparatus A. Is attached. The detailed structure of the shutter mechanism 24 will be described later.

The lower surface of the lower frame 15 also serves as a guide for conveying the recording medium. Here, the lower surface of the lower frame body 15 that functions as a conveyance guide of the recording medium will be described more specifically.

As shown in FIG. 39, the guide portion 15h on the lower surface of the lower frame 15 on the upstream side in the recording medium conveyance direction is directed to the tangential direction N ₁ at the nip position N between the photosensitive drum 9 and the transfer roller 6, as shown in FIG. Te only L _a = 5.0 to 7.0 mm approximately dimension of a certain state to deflect the recording medium P. Since the guide portion 15h is the lower surface of the lower frame 15 configured to have the space necessary for supplying the developing sleeve 12d and the toner to the sleeve 12d, it is determined to obtain appropriate developing conditions. determined by position of the developing sleeve 12d, the closer it to nip tangential N ₁ is the bottom frame 15 becomes thinner, there is a strength problem of the process cartridge B.

Further, the lower end position 13 of the cleaning means 13 located on the lower surface of the lower frame 15 on the downstream side in the recording medium conveying direction.
f is the cleaning blade 13a or the squeeze sheet 13
a distance L _b that is determined by the arrangement necessary for configuring the cleaning means 13 such as b and does not interfere with the recording medium P being conveyed.
= 4.5 to 8.0 mm (about 6.2 mm in this embodiment). In this embodiment, the vertical line from the rotation center of the photosensitive drum 9 shown in FIG.
And an angle δ = 10 to the line connecting the rotation centers of the transfer roller 6
It is set to 30 ° (about 20 ° in this embodiment).

(Shutter Mechanism) The photosensitive drum 9 is exposed through an opening 15g (see FIG. 42) provided in the lower frame 15 and faces the transfer roller 6 in order to transfer the developing toner onto the recording medium. However, in the state where the process cartridge B is removed from the image forming apparatus A, if the photoconductor drum 9 is exposed, the photoconductor drum 9 is exposed to external light and deteriorates, and the drum 9 is exposed. Dust will adhere. Therefore, the process cartridge B has a shutter mechanism 24 that protects the exposed portion of the photosensitive drum 9 from external light and dust when it is removed from the image forming apparatus A. Hereinafter, the configuration of the shutter mechanism 24 will be described in detail with reference to FIGS. 40 to 44.

<Structure of Shutter Mechanism> The Shutter Mechanism
As shown in FIG. 40, reference numeral 24 denotes a shutter arm 24a, a shutter joint 24b, a shutter portion 24c, and shaft holders 24d, 24.
e and a torsion coil spring 24f, which automatically opens when the process cartridge B is mounted in the image forming apparatus A, and automatically closes when the cartridge B is taken out.

The shutter arm 24a is made of metal,
As shown in FIG. 40, the vicinity of both ends of the shaft portion 24a1 is rotatably supported by the support portions 24d1 and 24e1 (see FIG. 43) of the shaft retainers 24d and 24e. This shutter arm 24a
The shutter joint 24b is rotatably supported by
The shutter joint 24b has a rotation center portion 24b1 by the rotation restricting portion 24a2 of the shutter arm 24a, which is indicated by an arrow d _{1 in} FIG.
It is restricted so that it does not rotate more than a certain angle in the direction.
Although the shutter portion 24c in the shutter linkage 24b is rotatably supported, arrow e ₁ in FIG. 40 the shutter portion 24c has its rotation center 24c1 by the rotation regulating portion 24b2 of the shutter linkage 24b It is restricted so that it does not rotate more than a certain angle in the direction.

Further, the shaft pressing member 24d that rotatably supports one end of the shutter arm 24a has a supporting portion 24 thereof.
A torsion coil spring 24f is fitted in a protruding portion 24d2 (see FIG. 43) formed by protruding from d1. One end of the torsion coil spring 24f is hooked on the groove 24d3 of the shaft retainer 24d, and the other end is hooked on the support 24a3 of the shutter arm 24a that rotatably supports the shutter joint 24b. A rotation moment in the direction of arrow f shown in FIG. 41 is applied. Therefore, the with the torsion coil spring 24f the shutter arm 24a of the rotation restricting portion 24a2 by the biasing force of regulating the shutter linkage 24b in the arrow d ₂ direction in FIG. 41, the rotation restricting portion 24b2 of the shutter linkage 24b the shutter portion 24c is regulated in the arrow e ₂ direction in FIG. 41, the shutter mechanism
24 becomes fully closed as shown in FIG.

In the present embodiment, when the shutter mechanism 24 is in the fully closed state, even if the shutter portion 24c contacts the photosensitive drum 9, the surface of the drum is not damaged.
The inner surface side (drum surface side) is molded smoothly. Further, in this embodiment, as shown in FIG. 42, shutter support portions 14k are provided at both longitudinal ends of the drum opening 15g in the lower frame body 14, and when the shutter mechanism 24 is in the fully closed state, the shutter portion is closed. The shutter support portion 14k holds 24c so that the surface 24c does not contact the surface of the photosensitive drum 9.

The shutter mechanism 24 can be attached to and detached from the upper frame body 14. That is, as shown in FIG. 43, locking pawls 24d4 and 24e4 are provided on shaft retainers 24d and 24e that rotatably support the shaft portion 24a1 of the shutter arm 24a, and the locking pawls 24d4 and 24e4 are attached to the upper frame 14a. The shutter mechanism 24 is attached to the upper frame body 14 by being locked in locking openings (not shown) provided at both ends in the longitudinal direction of the upper surface of the developing side.

<Amount of Engagement of Locking Claw for Shaft Pressing> The shutter mechanism 24 is configured to be opened and closed when the cartridge is attached and detached. When opening and closing the shutter mechanism 24, the shutter mechanism 24 is locked and fixed to the upper frame body 14. The force applied to the shaft holders 24d and 24e that are being changed changes. One of the shaft retainers 24d and 24e
Since the torsion coil spring 24f that biases the shutter mechanism 24 in the closing direction is applied to d, the force applied is larger than that of the other shaft retainer 24e to which the spring 24f is not applied, and its change. Is also big. Therefore, the engaging amount of the locking claw 24d4 of the shaft retainer 24d is equal to the engaging claw 24e4 of the other shaft retainer 24e.
There is a possibility that it will come off with the same hanging amount. Therefore,
In this embodiment, the engagement amount of the locking claw 24d4 of the shaft retainer 24d is made larger than the engagement amount of the retaining claw 24e4 of the shaft retainer 24e so that the shaft retainer 24d is prevented from coming off. More specifically, the engagement amount of the locking claw 24d4 of the shaft retainer 24d in this embodiment is larger in one engagement amount than in the other engagement amount. That is, the shaft retainer 24
d and 24e are provided at both longitudinal ends of the upper frame body 14,
The shaft retainer 24d on one end side provided with a spring 24f for urging the shutter portion 24c in the closing direction has a different hooking amount of the locking claw 24d4, and is provided on the other end side where the spring 24f is not provided. The engagement amounts of the locking claws 24e4 of the shaft retainer 24e are equal. Therefore, the locking strength with respect to the upper frame 14 of the shaft retainers 24d and 24e is different.

The concrete numerical values of the engagement amounts of the locking claws 24d4 and 24e4 in the present embodiment are shown below, but the present invention is not limited to this and can be appropriately selected.

(1) Engagement amount of one pawl of the locking pawl 24d4 of the shaft retainer 24d (D1) → about 1.0 mm (2) Engagement amount of the other pawl of the engaging pawl 24d4 of the shaft retainer 24d (D2) → Approximately 1.1 mm (3) Arm length of locking claw 24d4 of shaft retainer 24d (D3) → Approx. 2.8 mm (4) Engagement of one claw of locking claw 24e4 of shaft retainer 24e (E1) → Approx. mm (5) Engagement of the other claw of the locking claw 24e4 of the shaft retainer 24e (E2) → about 1.0 mm (6) Arm length of the locking claw 24e4 of the shaft retainer 24e (E3) → about 2.8 mm

<Rotation Center of Shutter Mechanism> Further, the shutter mechanism 24 has the shutter arm 24a which is the rotation center thereof.
Since the shaft portion 24a1 is bridged in the longitudinal direction of the upper surface of the upper frame 14 on the developing side, the shaft portion 24a1 may be deformed by the user pulling the shaft portion 24a1 by hand when the cartridge is mounted. Further, in this embodiment, as shown in FIG.
The lid member 12f has a bulge portion to increase the toner volume of 12a.
Since 12f3 is provided, if the shaft portion 24a1 which is the rotation center of the shutter mechanism 24 is bridged over the bulging portion 12f3, the rotation range of the shutter mechanism 24 becomes large. Therefore, in order to prevent these, in this embodiment, as shown in FIG. 44, the groove portion is formed over the longitudinal direction of the bulge portion 12f3 of the lid member 12f.
12f4 is provided, and the shaft portion 24a1 is passed through the groove portion 12f4 so as not to protrude from the upper surface of the bulge portion 12f3 of the lid member 12f.

{Assembly Structure of Process Cartridge} Next, the assembly of the process cartridge B having the above structure will be described in detail with reference to the drawings.

(Incorporation into Lower Frame) As shown in FIG. 45, first, the developing sleeve seal seat surface 15i of the lower frame 15 is installed.
And a sealing member S _{4 made of} polyurethane foam or the like having a fixed shape for preventing toner leakage at the step portion 15j1 on the outer side in the longitudinal direction of the cleaning blade mounting seat surface 15j.
Stick S ₅ with double-sided tape. In the present embodiment use a felt member as the seal member S ₄ that is stuck to the developing sleeve seal bearing surface 15i, using foamed polyurethane as a sealing member S ₅ of attaching the step portion 15j1 of the cleaning blade mounting seat surface 15j is doing. It should be noted that the seal members S ₄ and S ₅ for preventing toner leakage do not have to be regular ones,
A recess may be formed in a portion of the frame to which the seal member is attached, and a liquid substance that is solidified and becomes an elastomer may be injected into the recess to attach the toner leakage prevention seal.

Next, the developing sleeve 12d is attached to the lower frame body 15 to which the seal member S ₄ is attached. As described above, the seal member S ₄ prevents the toner from leaking at the end of the developing sleeve 12d. However, as shown in FIG. 46, the developing sleeve 12d is rotated in the direction of rotation (in the direction of the arrow in the drawing) and the roll inside the sleeve. from the relationship between the magnetic poles of the magnet 12c, since the the developing sleeve 12d end portion of the seal member S ₄ near the toner as indicated by the shaded portion of FIG. 46 attached, the sealing member S ₄
The sealing function of must be highest in the lower part 15i1 shown in FIG. Therefore, the sleeve seal seat surface 15i in this embodiment is molded so that the radius R1 from the center position of the developing sleeve 12d to the lower portion 15i1 of the sleeve mounting seat surface 15i is smaller than the radius R2 of the other portions.
That is, the relationship of the radii is R1 <R2. Therefore, the developing sleeve 12d dual bearing 12h, when attached to the bottom frame 15 through 12i, the seal member S ₄ at the lower portion 15i1 is crushed more than other portions, the sealing pressure against the developing sleeve 12d in the lower 15i1 It becomes higher and the sealing function is improved. Incidentally, the sleeve seal seat surface 15i in the present embodiment
Is molded so that the seal member S ₄ in the lower portion 15i1 is crushed by about 0.4 mm more than the other portions.

Next, the blade supporting member 12e1 having the developing blade 12e attached thereto and the blade supporting member 13a1 having the cleaning blade 13a attached thereto are attached to the respective blade attaching surfaces 15k and 15j of the lower frame 15 by screws 12e2 and 13a2, respectively. At this time, in the present embodiment, as shown by the broken line in FIG. 45, the blade supporting members 12e1, 13a1 are arranged so that the screws 12e2, 13a2 can be screwed in the same direction.
The blade mounting seat surfaces 15k and 15j are configured to be substantially parallel to each other. Therefore, when the process cartridge B is mass-produced, the screwing of the developing blade 12e and the cleaning blade 13a can be continuously performed by an automatic machine or the like. This secures a space for a screw rotating driver and the like to improve the assemblability of both blades 12e and 13a, and simplifies the die structure by aligning the die removing directions of the die for molding the housing (frame body). The cost can be reduced.

In this embodiment, the developing blade mounting seat surface 15 is used.
The angle of k is approximately 24 ° with respect to the vertical line shown in FIG. 45, and the angle of the cleaning blade mounting seat surface 15j is approximately 22 ° with respect to the vertical line shown in FIG. 45. I am configuring. Further, as described above, both blades 12e,
Since the screwing of 13a is performed continuously by an automatic machine,
The angle of the fixing screw holes provided on each of the blade mounting seat surfaces 15k and 15j is about two with respect to the horizontal line shown in FIG.
It is 24 °, which is the angle that can be pulled out with the same slide.

The developing blade 12e and the cleaning blade 13a may be attached to the lower frame 15 by adhesives 12e4 and 13a3 as shown in FIG. good. Also in this case,
If the bonding can be performed from the same direction, the developing blade 12e and the cleaning blade 13a can be continuously attached by an automatic machine or the like as in the case of screwing.

<Cleaning Blade End Seal> Further, as shown in FIG. 49, a seal member S ₆ made of polyurethane foam is attached to the lower part of the blade mounting seat surface 15j corresponding to the end of the cleaning blade 13a. This is because the toner scraped off by the cleaning blade 13a is
This is a seal for running over 13a and preventing it from leaking from its end.

[0151] To reduce the size of the time the process cartridge B, the distance between the lower corner portion of the seal member S ₆ as shown in FIG. 50, a point in contact with the photosensitive drum 9 and the seal member S ₆ L _{If s} becomes short (specifically, 0.5 mm or less), the seal member S ₆ may be caught in the photosensitive drum 9 due to the rotation torque or vibration of the photosensitive drum 9. It may come off. Therefore, the seal member S ₆ in this embodiment is
Above the high density polyethylene sheet 37 as shown in FIG. 49.
Affixed to the photosensitive drum 9 and the seal member S ₆
The friction resistance of is reduced to prevent entrainment.

Further, the cleaning blade 13a is coated with a solid lubricant 38 such as polyvinylidene fluoride (PVDF), carbon fluoride, or silicon fine powder, and adheres to the photosensitive drum 9 in the initial state without toner. However, in the present embodiment, the lubricant 38 is also applied to the seal member S ₆ as shown in FIG. 51. As a result, the drum end and the seal member S are
The frictional force with ₆ is further reduced, and the entrainment of the seal member S ₆ is prevented.

<Developing Blade End Seal> Further, as shown in FIG. 52, the toner is _discharged from the gap L _t formed between the end of the developing blade 12e and the lower frame 15 (the end surface of the seal member S ₄ in FIG. 52). To prevent toner from leaking and developing sleeve 12d
In order to scrape off the toner layer in the above gap L _t ,
Sealing members S ₇ are arranged at both ends of the developing blade 12e. The seal member S ₇ is formed so as to follow the shape of the developing blade 12e pressed by the developing sleeve 12d as shown in FIG.
The structure is such that the pressing force against 12d is not increased. As a result, the seal member S ₇ has its upper portion S ₇₁
In preventing toner leakage, and scrapes off the toner on the developing sleeve 12d edge under side S _72.

As described above, the photosensitive drum 9 is attached after the blades 12e and 13a are attached. Therefore, in this embodiment, as shown in FIG. 45, the developing blade support member 12e1
And the guide member 15q on the lower frame body 15 on the surface of the cleaning blade supporting member 13a1 facing the photoconductor drum and outside the image forming region in the longitudinal direction of the photoconductor drum 9 (region L _{d in} FIG. 54).
There are 1, 15q2. The distance L _g between the guide members 15q1 and 15q2 is set to be larger than the outer diameter R _d of the photosensitive drum 9.

For this reason, the photosensitive drum 9 is mounted with the blades 12e, 13a and the like attached to the lower frame 15, and
As shown in FIG. 45, the guide members 15q1 and 15q2 can be attached last while guiding the vicinity of both ends in the longitudinal direction (outside the image forming area). That is, the photosensitive drum 9 slightly bends the blade 13a, and the developing sleeve 12
It is attached to the lower frame 15 while allowing d to escape a little and rotating.

When the photosensitive drum 9 is first attached to the lower frame body 15 and then the respective members such as the blades 12e and 13a are attached, the surface of the photosensitive drum 9 is attached to the blades 12e and 13a. May hurt. In addition, there is a problem in that it is impossible to inspect the mounting position of the developing blade 12e and the cleaning blade 13a and the measurement of the contact pressure on the photosensitive drum 9 during assembly. Further, in the initial state in which both blades 12e and 13a have no toner, a lubricant is applied to prevent the torque from being increased and the blades are turned up due to the close contact with the photosensitive drum 9 and the developing sleeve 12d. This must be done before attaching to the body 15, but at this time, there is a problem that inconvenience such as slipping-off of the lubricant during assembly is likely to occur. In this respect, the above-mentioned inconvenience can be solved by incorporating the photoconductor drum 9 at the end as in the present embodiment.

As described above, according to this embodiment, the developing means
It is possible to perform an inspection such as measurement of a mounting position with the 12 and the cleaning unit 13 mounted on the frame body, and further, it is possible to prevent scratches and dents in the image forming area when the photosensitive drum is mounted. Also, with the developing means 12 and the cleaning means 13 attached to the frame, it is possible to apply a lubricant to them, and therefore the lubricant can be prevented from falling off, the developing blade 12e, the developing sleeve 12d, and the cleaning blade. There is an effect of preventing torque increase and blade flipping due to the close contact between 13a and the photosensitive drum 9.

In this embodiment, the lower frame 15 is provided with the drum guide members 15q1 and 15q2 which are integral or separate, but as shown in FIG. 55, the blade support members 12e1 and 13a1 are provided.
Of the blade support members 12e1, 13a1 or separate protrusions 12e5, 13a4 provided at both ends in the longitudinal direction of the photosensitive drum 9 outside the image forming area. You may make it function as.

<Method of Mounting Photosensitive Drum> In this embodiment, the method of mounting the photosensitive drum 9 is carried out by a predetermined angle γ with respect to the contact surface of the cleaning blade 13a as shown in FIG.
I am trying to do it. This is because the lubricant 38 applied as described above is applied to the tip of the blade 13a so as to macroscopically uniformly cover the edge portion of the blade tip, but it is microscopically shown in FIG. This is because there is an uncoated region L _c having a width of several tens of microns near the edge portion as shown in (a).

Therefore, by mounting the photosensitive drum 9 as described above, the lubricant 38 on the cleaning blade 13a is
As shown in FIG. 56 (b), the drum 9 and the blade 13 are
After the contact with a, the photosensitive drum 9 disperses so as to be dragged along with the invasion of the photosensitive drum 9, and reaches the region L _c where the lubricant 38 has not been applied. It will exist on the entire contact surface with the blade 13a.

The mounting direction of the drum 9 is the blade 13
Although it is performed with a predetermined angle γ with respect to the contact surface of a, when the present inventor conducted experiments, it was found that blade
When the rubber hardness of 13a is 60 degrees or more and the penetration amount is 0.5 mm or more, or when the contact thickness of the blade 13a with the drum 9 is 15 gf / cm or more, the drum 9 is used.
It has been found that the above-mentioned effect can be obtained when the invasion angle γ of is less than 45 degrees with respect to the contact surface of the blade 13a. In this embodiment, the drum is mounted with an angle γ of about 22 degrees.

<Incorporation of Drum Support Shaft and Bearing Member> As described above, the developing sleeve 12d, the developing blade 12e,
The cleaning blade 13a and the photosensitive drum 9 are attached to the lower frame 15
57 and a sectional view of FIG. 22, the drum support shaft 9d having the support portion 9d4 and the bearing member.
By attaching 16 to both ends of the photosensitive drum 9,
The drum 9 is rotatably attached to the lower frame 15.
The bearing member 16 is made of a slidable material such as polyacetal, and has a drum bearing portion 16a fitted into the photosensitive drum 9 and a sleeve bearing portion for roughly guiding the outer diameter of the developing sleeve 12d.
16b and D The shaft end of the D-cut magnet 12c is fitted into D
The cut hole portion 16c is integrally molded.

Therefore, the bearing 16a is fitted into the end of the cylindrical photosensitive drum 9, and the end of the magnet 12c is inserted into the D cut hole.
The bearing member 16 is fitted in the side surface of the lower frame body 15 and fixed, so that the photosensitive drum 9 and the magnet 12c are axially supported. As shown in FIG. 57, the bearing member 16 is provided with a conductive ground contact 18a. When the bearing member 16 is fitted into the photosensitive drum 9, the ground contact 18a is made of an aluminum conductive base material of the photosensitive drum 9. 9a (see FIG. 10). A bias contact 18b is attached to the bearing member 16. When the bearing member 16 is attached to the developing sleeve 12d, the contact 18b is attached to the developing sleeve 12d.
The contact is made with the conductive member 18d which is in contact with the inner surface of the.

By thus supporting the photosensitive drum 9 and the magnet 12c by the bearing member 16 which is one component,
It is possible to improve the mounting position accuracy of both members 9 and 12c, reduce the number of parts, facilitate assembly, and reduce costs.

The positioning of the photosensitive drum 9 and the magnet 12c
By positioning the photosensitive drum 9 with one member,
Since the magnet 12c can be accurately positioned, the magnetic force on the surface of the photosensitive drum 9 can be kept constant, and a uniform and high-definition image can be obtained.

A drum ground contact 18a for grounding the photosensitive drum 9 to the bearing member 16 and a developing sleeve 12d.
By providing the developing bias contact 18b for applying a bias to the parts, the parts can be effectively downsized, and the process cartridge B can also be effectively downsized.

Further, the bearing member 16 is provided with a supported portion for positioning the process cartridge B in the main assembly of the image forming apparatus when the process cartridge B is mounted in the main body of the image forming apparatus. The position can be set accurately.

Further, as shown in FIG. 22, the bearing member 16 has a drum shaft portion 16d which is a cylindrical convex portion protruding outward.
When the process cartridge B is attached to the main assembly A of the apparatus, the shaft hole portion 15s of the lower frame body 15 into which the shaft portion 16d and the drum support shaft 9d on the other end side are press-fitted is formed as described below.
The process cartridge B is positioned by being supported by the substantially U-shaped slot portion 2a1 of the cartridge mounting portion 2. As described above, since the shaft hole portion 15s and the shaft portion 16d that directly support the photosensitive drum 9 perform positioning when the process cartridge B is mounted in the apparatus main assembly A, processing accuracy and assembly error of other members Positioning can be performed accurately without picking up.

Further, as shown in FIG. 22, the other end of the magnet 12c is received by a recess inside the sleeve flange 12k.
The outer diameter of 12c is slightly smaller than the inner diameter of the recess. Therefore, on the sleeve flange 12k side, the magnet 12c
Is held with play, and is held below by the weight of the magnet 12c, or is urged toward the blade support member 12e1 side by the magnetic force of the magnet 12c by the blade support member 12e1 made of a magnetic sheet metal such as a galvanized steel plate. There is.

As described above, the sleeve flange 12k and the magnet 12 are
By providing the c with play, the friction torque between the magnet 12c and the sleeve flange 12k that rotates and slides can be reduced, and the torque of the process cartridge itself can be kept low.

(Incorporation into Upper Frame Body) On the other hand, in the upper frame body 14, first, as described above, the sliding bearing 10c is attached to the bearing slide guide claw 14n via the spring 10a, and the sliding bearing 10c is charged. The roller 10 is rotatably attached. Further, a toner feeding mechanism 12b is attached in the toner reservoir 12a, and a cover film 26 having a tear tape 25 shown in FIG. 58 is attached to the opening 12a2 for feeding the toner from the toner reservoir 12a to the developing sleeve 12d. 12a2 is closed, the lid member 12f is welded, the toner is stored in the toner reservoir 12a, and the toner reservoir 12a is closed. Further, a shutter mechanism 24 is attached to the upper part of the upper frame 14 on the developing side so as to be openable and closable. As described above, the shutter mechanism 24 has a shaft portion in the groove portion 12f4 of the lid member 12f.
Both ends of 24a1 are attached by shaft retainers 24d and 24e (see FIG. 44).

<Tear tape> Opening of the toner reservoir 12a
Tear tape provided on the cover film 26 attached to 12a2
As shown in FIG. 58, 25 (for example, polyethylene terephthalate or polyethylene) extends from the longitudinal end (the right end in FIG. 58) of the opening 12a2 to the other end (the left end in FIG. 58), It is folded back at the other end and exposed to the outside through an opening 14f as a gap formed in the rear end of the upper frame 14. Since the opening 14f is provided so that the tear tape 25 comes to the front side of the operator when the process cartridge B is attached to the apparatus main body A, the tear tape 25 comes into the operator's field of view, and its existence. Become easier to notice (see Fig. 44). Furthermore, the color of the tear tape 25 is set to the frame 1
It is possible to improve the visibility and reduce forgetting to pull out by changing the colors of 4 and 15 that are more conspicuous, for example, by using white, yellow or orange when the frame is black. .

The direction in which the tear tape 25 is pulled out in order to improve the workability of the operator is approximately the same as the direction in which the process cartridge B is incorporated in the apparatus main assembly A (arrow g ₁ direction) as shown in FIG. Opposite direction (arrow g ₂ direction)
It has become. As a result, for example, when the operator holds the process cartridge B with the left hand and pulls the tear tape 25 toward the front with the right hand, the operator can mount the process cartridge B on the image forming apparatus A without holding the process cartridge B. . Further, even if the operator forgets to pull out the tear tape 25 and mounts the process cartridge B in the image forming apparatus A, he / she takes out the process cartridge B from the image forming apparatus A and changes his / her hand. It is possible to pull out the tear tape 25 without it.

When a new process cartridge B is used, the tear tape 25 exposed from the opening 14f is pulled to peel off the cover film 26 attached to the opening 12a2 of the toner reservoir 12a to remove the toner reservoir. The toner in 12a is moved in the direction of the developing sleeve 12d and then mounted in the image forming apparatus A.

(Sealing Member of Upper and Lower Frames) Next, the sealing member attached to the seam of the upper frame 14 and the lower frame 15 will be described. As shown in FIGS. 37 and 38,
A seal member is attached to the joint between the upper frame body 14 and the lower frame body 15. Sealing members S ₁ , S ₂ and S ₃ are attached to the upper frame body 14, and sealing members S ₈ and S ₉ are attached to the lower frame body 15.
This seal member prevents toner leakage from the joint between the upper and lower frames 14 and 15. In this embodiment, it is the seal member S ₁ that prevents toner leakage from the joints of the cleaning means-side frames 14 and 15, and the toner leakage from the joints of the developing means-side frames 14 and 15. The sealing members S ₂ , S ₃ and S ₈ , S ₉ prevent the above.

<Groove and rib at seam of upper and lower frames>
As described above, the seal member for preventing toner leakage to the outside of the process cartridge B is attached to the joint between the upper frame body 14 and the lower frame body 15. As shown in FIG. Grooves are provided on the seating surface of the 14 sealing members S ₁ , S ₂ , S ₃
14 m is provided, and a triangular rib 15 r is further provided at a portion of the lower frame 15 that faces the seal members S ₁ , S ₂ , and S ₃ . Therefore, the combination of the upper and lower frames 14 and 15, the sealing member S ₁ as shown in FIG. 53,
S ₂ and S ₃ are crushed into a wave shape. As a result, the sealing property of the seam between the upper and lower frames 14 and 15 by the sealing member is improved. At this time, since the seal member and the like are locally crushed, the reaction force hardly increases, and the frame body 14,
It does not impair the unity of 15. In this way, the upper and lower frame
When the upper and lower frame bodies 14, 15 are joined by interposing the seal members S ₁ , S ₂ , S ₃ between the 14, 15, the seal members S ₁ , S ₂ , S ₃ are locally compressed. Upper and lower frame
The process cartridge B is assembled by connecting 14 and 15.

Further, pressure is applied to the toner inside the process cartridge due to an external factor (for example, vibration or shock), and the above-mentioned joints of the upper and lower frame bodies 14 and 15 in which the seal members S ₁ , S ₂ and S ₃ intervene. since the toner under pressure. However invading the said triangular projection 15r, by the repulsive force of the being locally compressed seal member S _1, S _2, S ₃ by the ribs 15r, the progress is hampered, The upper and lower frames
The toner will not leak to the outside of 14 and 15.

Incidentally, the seal members S ₁ , S in this embodiment are
_Although foamed polyurethane such as Moltoprene (trade name) is used as the material for ₂ and S _3, a liquid material that solidifies into an elastomer and is injected into the groove 14m may be used as a sealing member.

Further, the shape of the protrusion may be a shape which locally compresses the seal member even if the sectional shape is not triangular. Further, the groove provided on the sticking seat surface of the seal member may be omitted. By the way, in this embodiment, the thickness of the seal member is about 3 mm, and the seal member is compressed to about 1 mm. At this time, the height of the protrusion is about 0.5 mm.

<Hardness of Seal Member> Also, the upper and lower frame members 1
The seal members S ₁ , S ₂ , attached to the 4 and 15 joints,
For S ₃ , the seal members S ₂ and S ₃ on the developing unit side are harder than the seal member S ₁ on the cleaning unit side. This is because the developing device side is more likely to bend than the cleaning device side in the longitudinal direction of the process cartridge B. In this embodiment, a seal member corresponding to the mesh 60 (# 60) is used as the seal member S ₁ on the cleaning unit side, and a seal member corresponding to the mesh 120 (# 120) is used as the seal members S ₂ and S ₃ on the developing unit side. I'm using it. The sealing members S ₁ , S ₂ and S ₃ have a thickness of about 3 m.
About m, the required sealing performance is secured by crushing this to about 1 mm when the upper and lower frames 14, 15 are combined. This is the sealing property and the upper and lower frames 14, 15
It is an optimal value that combines both of the unity of.

<Bearing of Tear Tape> As described above, the seal members S ₈ and S ₉ are attached to both ends of the lower frame 15 in the longitudinal direction on the developing means side. Of the seal members S ₈ and S ₉ , the seal member S ₈ on the pull-out side of the tear tape 25 has an upper frame body 14 and a lower frame body as shown in FIG.
Widely curved and affixed to the folding curved surface 15t of the lower frame body 15 extending from the inside of the cartridge to the outside of the cartridge at the joint (the position of the broken line in FIG. 59) with 15. As a result, when the operator pulls out the tear tape 25 from the process cartridge B, the tear tape 25 is attached to the upper frame body 14 and the lower frame body 15 which is an opposing portion thereof.
It is pulled out to the outside of the cartridge through the space between the seal members S ₈ which are widely attached to the bent curved surface 15t. Therefore, the tear tape 25 always in the seal member S ₈ will be per belly, at the same time to prevent the seal member S ₈ is peeled pulled by pulling the tear tape 25, to lower the pulling force of the tear tape 25 It will be possible.

[0182] That is, by tear tape 25 is in contact with the curved arc portion of the seal member S _8, since no contact to the end portion of the seal member S _8, tear tape
The seal member S ₈ is not peeled off when the 25 is pulled out. The tear tape 25 is pulled out in the direction of the opening 12
By attaching the tear tape 25 to the opening peripheral edge so as to block a2, in a direction different from the extension of the attaching surface,
When the tear tape 25 is pulled out, the tear tape 25 does not come into contact with the end of the elastic seal member S ₈ . According to this embodiment, so as not to contact with the end portion of the seal member S ₈ when pulling out the tear tape 25, be removably attached to the tear tape 25 for closing the opening 12a2 to the aperture 12a2 You can

The upper frame body 14 in which the respective parts are incorporated as described above.
The lower frame 15 and the lower frame 15 are mutually locked by the locking claws and the locking openings described above, and the two frames 14 and 15 are coupled to assemble the process cartridge B. Here, the assembly and shipping line of the process cartridge B will be described with reference to FIG. Each frame is assembled into the lower frame 15 and the lower frame 15 is assembled.
(For example, the positional relationship between the photosensitive drum 9 and the developing sleeve 12d) is performed. And this lower frame 15 and charging roller 10
This is a simple line in which the process cartridge B is assembled by combining with the upper frame body 14 in which parts such as the above are incorporated, and after the overall inspection of the entire cartridge B, the process cartridge B is shipped.

{Mounting Structure of Process Cartridge} Next, the mounting structure of the process cartridge B to the image forming apparatus main body A will be described with reference to the drawings.

(Process Cartridge Mounting Guide) To mount the process cartridge B on the image forming apparatus A, first, an upper opening / closing cover 1b is provided on the upper part of the apparatus main body 1 so as to be openable / closable about a shaft 1b4 as a rotation center. 61 as shown in FIG. 61, and the process cartridge B is inserted into the cartridge mounting portion 2 inside the apparatus main body from the direction of the arrow in FIG. At this time, as shown in FIG. 62, the process cartridge B has a lower frame 15 protruding from both outer side surfaces in the longitudinal direction thereof.
15s of the shaft hole and the shaft part 16d of the bearing member 16, and the shaft hole 15
s and the shaft portion 16d, the first guide portion provided on both inner side surfaces of the mounting portion 2 is provided with the first engaging portion 14q provided so as to be directed rearward (right side in FIG. 62) in the cartridge insertion direction. 2a, and second engaging portions 15u provided on both sides in the longitudinal direction of the lower front portion in the insertion direction of the cartridge B,
14r is inserted while being guided by the second guide portions 2b provided on both inner side surfaces of the mounting portion 2.

The second engaging portion 15u, which is the protruding portion, is arranged on the same side as the flange gear 9c provided on the photosensitive drum 9. The second engaging portion 15u is a cleaning means 13 provided along the axis of the photosensitive drum 9.
About 2.7 mm more than the lower frame body 15 on the side in the direction orthogonal to the axis of the photosensitive drum 9 (the front end direction when the process cartridge B is attached to the apparatus main body). Furthermore, the engaging portion 15u is flat and has a taper 15u1 (see FIGS. 4 and 5) provided below. Further, the engaging portion 15
u projects further downward by about 6 mm from the lower surface of the lower frame 15 on the cleaning means 13 side.

When inserting the cartridge B,
As shown in FIG. 62, even if the process cartridge B is pushed down in the insertion direction forward (counterclockwise rotation direction) about the shaft hole portion 15s and the shaft portion 16d, the second engagement portion 15
Since u, 14r and the second guide portion 2b are in contact with each other, they are not pushed down, and conversely, the shaft hole portion 15s and the shaft portion 16d.
Even if an attempt is made to push down the cartridge B in the insertion direction rearward (clockwise direction) at the time of insertion, the first engaging portion
14q comes into contact with the first guide portion 2a and does not push down further.

When the cartridge B passes over the transfer roller 6, as shown in FIG. 63, the second engaging portion
Since 15u pushes down the shaft 6d portion at one end of the transfer roller 6, the lower front portion in the cartridge insertion direction does not come into contact with the transfer roller 6 and the like, and there is no fear of damaging them. At this time, the second engaging portion 14r at the other end is in contact with the second guide portion 2b. Then, when the process cartridge B is further inserted into the back of the apparatus main body, the second engaging portion 15
u and the transfer roller shaft 6d are disengaged, and the transfer roller 6
Is pushed upward by the spring 6b and then pressed against the photosensitive drum 9.

Therefore, the process cartridge B is smoothly inserted while being guided by the guide portions 2a, 2b, and as shown in FIG. 1, the shaft hole portion 15s and the shaft portion 16d are closed when the upper opening cover 1b is closed. The first guide portion 2a is fitted and positioned in a substantially U-shaped groove hole portion 2a1 provided at the most downstream portion in the cartridge insertion direction.

(Operation of Shutter Mechanism when Cartridge is Installed) The process cartridge B is provided with the shutter mechanism 24 for protecting the surface of the photosensitive drum 9.
The shutter mechanism 24 according to the present embodiment is configured to automatically open when the process cartridge B is attached to the image forming apparatus A. The operation of the shutter mechanism 24 when the cartridge is mounted will be described below.

As described above, when the process cartridge B is inserted into the image forming apparatus A, the protrusion provided on the side of the supporting portion 24a3 of the shutter arm 24a at the position shown in FIG.
24a4 (see FIG. 40) is the shutter cam surface 2 on the upper surface of the main body of the apparatus.
touch c. When the process cartridge B is further inserted from this state, the protrusion 24a4 of the shutter arm 24a
Moves on the shutter cam surface 2c to the right in FIG. In conjunction with this, the shutter joint 24b and the shutter section 24
c also moves to the right, and the surface of the photosensitive drum 9 is exposed away from the lower portion of the lower frame 15 as shown in FIG. At this time, the shutter joint 24b is released from the rotation restriction by the rotation restriction portion 24a2 of the shutter arm 24a.
The shutter 24c is in a state of hanging by its own weight on the supporting portion 24a3 of the 24a and is in contact with the inside of the main body of the apparatus and is stopped. However, the rotation regulation of the shutter coupling 24b by the rotation regulating portion 24b2 of the shutter joint 24b is still released. Not in a position.

When the process cartridge B is further inserted, the projection 24a4 of the shutter arm 24a has moved to the right on the shutter cam surface 2c, and then starts to move to the left. 24a support 24
The shutter joint 24b hanging from a3 by its own weight starts to rotate counterclockwise around the contact portion with the inside of the apparatus main body. When the shutter joint 24b rotates to a state in which the shutter joint 24b is almost vertical, the shutter portion 24c that has been rotating integrally with the shutter joint 24b comes into contact with the inside of the apparatus main body, and the rotation regulating portion 24b2 of the shutter joint 24b is used. When the upper opening / closing cover 1b of the apparatus main body is closed after the rotation restriction is released and the cartridge is inserted, the shutter mechanism 24 is moved to the position shown in FIG.
As shown in FIG.
Come into contact with.

As described above, the shutter mechanism in this embodiment
The 24 not only opens automatically when the cartridge is installed, but also changes according to the shape inside the device body. In addition, it can be opened up to a position far from the drum in a space-saving manner, which can contribute to downsizing of the entire apparatus.

(Relationship Between Electrical Contact and Contact Pin) In the process cartridge B, the contact 18a for the conductive drum ground contacting the photosensitive drum 9, the contact 18b for the conductive developing bias contacting the developing sleeve 12d, and the charging. Laura 10
A contact 18c for conductive charging bias that is in contact with is provided so as to be exposed from the lower surface of the lower frame 15. Therefore, by mounting the process cartridge B on the apparatus main assembly A as described above, the respective contacts 18a, 18b, 18c are connected to the apparatus main body side drum grounding contact pin 27a, developing bias contact pin 27b, and charging as shown in FIG. It is pressed against the bias contact pin 27c.

As shown in FIG. 65, the contact pins 27a to 27c have a structure in which the contact pins 27a to 27c are attached to the holder cover 28, respectively.
It is attached so that it cannot fall out and can project, and the holder cover
Wiring pattern of electrical board 29 to attach 28 and each contact pin
27a to 27c are electrically connected by a conductive compression spring 30.

The arrangement of the electric contacts of the process cartridge B will be described below with reference to FIG. Incidentally, FIG. 66 is a plan view schematically showing the positional relationship between the photosensitive drum 9 and the electric contacts 18a, 18b, 18c.

Now, the contacts 18a, 18b, 18c are as shown in FIG.
As shown in FIG. 5, the flange gear 9c is arranged on the opposite side (non-driving side) from the side (driving side), and the photosensitive drum 9 is sandwiched between the recording medium conveying direction downstream side (cleaning means side). The charging bias contact 18c is disposed at the upstream side of the photosensitive drum 9 in the recording medium conveying direction (developing means side) and the drum grounding contact 18a and the developing bias contact 18c.
18b is arranged.

Further, the contact points of the contacts 18a, 18b, 18c with the contact pins 27a, 27b, 27c on the apparatus main body side are positioned so as not to overlap in the direction of inserting the process cartridge B (the direction of the arrow in the figure). It is arranged (y in Fig. 66)
3, y4). That is, the contact is the charging bias contact 18
c, contact 18a for drum ground, contact 18b for developing bias
In this order, the contact 18c for the charging bias is the contact pin for the drum ground inside the main body of the apparatus.
27a and the developing bias contact pin 27b are arranged at a position where they do not interfere with each other, and the drum ground contact 18a is arranged at a position where they do not interfere with the developing bias contact pin 27b inside the apparatus main body. This is to prevent the contact penetrating into the inner part of the device from coming into contact with the contact pin on the front side of the device body and being scratched or damaged, resulting in contact failure.

By arranging the respective contact positions so as not to overlap in the insertion direction of the process cartridge B as described above, the interference between the contact of the apparatus main body side and the contact of the process cartridge when the process cartridge is attached or detached is avoided. Can be independently set under optimum conditions, which facilitates downsizing of the apparatus main body and the process cartridge.

Of the above contacts, a contact for drum grounding
The electrode shape in the process cartridge can be simplified by providing 18a and the developing bias contact 18b at a position closer to the developing unit than the photosensitive drum 9 and providing the charging bias contact 18c at a position closer to the cleaning unit. The process cartridge can be downsized.

More specifically, the developing bias contact 18b corresponds to the drum ground contact 18a with respect to the photosensitive drum 9.
Is located farther than. The ground contact 18
The exposed area of "a" is larger than the exposed area of the developing bias contact 18b. Further, the exposed shape of the contact 18b for developing bias is a shape in which a semicircular portion is projected in a part of a rectangular parallelepiped. Further, the exposed shape of the ground contact 18a is a boot shape. Further, the exposed portion of the ground contact 18a is arranged from the portion facing the photosensitive drum 9 to the outside of the photosensitive drum 9. Further, the charging bias contact 18c
The exposed portion of is bent. Further, the contact 18b for developing bias and the contact 18a for ground are arranged so as to oppose the photoconductor application region (indicated by Z in FIG. 66) of the photoconductor drum 9.

Further, by providing the contact position of the process cartridge inside the outer shape of the process cartridge, it is possible to prevent foreign matter from adhering to the contact portion, rust of the contact due to this, or deformation of the contact due to external force.

Each size of the electrical contact according to this embodiment is illustrated, but the present invention is not limited to this, and can be appropriately selected.

(1) Distance between photoconductor drum 9 and drum ground contact 18a in the direction perpendicular to the drum center axis (X1) → about 3.9 mm (2) Drum between photoconductor drum 9 and charging bias contact 18c Distance in the direction perpendicular to the central axis (X2) → approx. 15.5 mm (3) Distance between the photosensitive drum 9 and the contact 18b for developing bias in the direction perpendicular to the drum central axis (X3) → approx. 23.5 mm (4) Photosensitive Distance between the body drum 9 and the drum ground contact 18a in the drum center axis direction (Y1) → about 11.5 mm (5) Distance between the photosensitive drum 9 and the charging bias contact 18c in the drum center axis direction (Y2) → about 1.5mm (6) Distance between the photosensitive drum 9 and the developing bias contact 18b in the direction of the drum center axis (Y3) → Approx. 3.1mm (7) Distance from the lateral end of the drum ground contact 18a to the contact center ( x1) → About 10.3mm (8) Vertical length of ram earth contact 18a (y1) → approx. 6.0mm (9) Horizontal length of charging bias contact 18c (x2) → approx. 12.4mm (10) Vertical length of charging bias contact 18c (y2) → approx. 6.5mm (11) Horizontal length of developing bias contact 18b (x3) → approx. 7.0mm (12) Distance from the vertical end of developing bias contact 18b to the contact center (y3) → approx. 6.1mm (13) For drum grounding Outer radius of contact 18a (r1) → about 3.0mm (14) Outer radius of contact 18b for developing bias (r2) → about 3.0mm (15) Contact point of contact 18b for developing bias and contact 18a for drum ground Deviation of contact point (y3) → approx. 5.0mm (16) Deviation of contact point of contact 18b for developing bias and contact 18c for charging bias (y4) → approx. 7.5mm

{Structure of holding process cartridge} As described above, the process cartridge B is guided to the guide portion 2a,
The process cartridge B must be securely fixed when it is inserted along the line 2b and the upper opening / closing cover 1b is closed. Therefore, in this embodiment, when the upper opening cover 1b is closed, the process cartridge B is pressed against the cartridge mounting portion 2 inside the apparatus main body.

As shown in FIG. 65, a biasing means 1b1 having a buffer spring is provided at a predetermined position on the inner top surface of the upper opening / closing cover 1b, and a leaf spring 1b2 is provided near the center of rotation of the upper opening / closing cover 1b. Is provided. The leaf spring 1b2 is not in contact with the process cartridge B to be inserted when the upper opening cover 1b is opened.

In the above construction, when the upper opening / closing cover 1b is opened, the process cartridge B is inserted along the guide portions 2a, 2b to a predetermined position and the upper opening / closing cover 1b is closed, as shown in FIG. The biasing means 1b1 provided on the inner top surface of the cartridge pushes the upper surface of the cartridge B downward, and the arm portion 1b3 of the upper opening / closing cover 1b pushes the leaf spring 1b2, and the leaf spring 1b2 lowers the upper surface of the cartridge B. Press to.

As a result, the cartridge B is positioned by pressing the shaft hole portion 15s and the shaft portion 16d against the groove hole portion 2a1 and the leg portions 15v1 and 15v2 provided so as to project to the lower portion of the lower frame body 15. The abutment portions 2b1 and 2b2 provided at predetermined positions of the second guide portion 2b are abutted and positioned, and the rotation of the cartridge B is restricted.

The leg portions 15v1 and 15v2 of the lower frame body 15 of the process cartridge B are provided at two positions, a driving side and a non-driving side, in the lower rear portion in the cartridge insertion direction (see FIG. 5).
Although the contact portions 2b1 and 2b2 are provided at two predetermined positions of the second guide portion 2b corresponding to the leg portions 15v1 and 15v2, both of the contact portions 2b1 and 2b2 are two. While the height is the same, the two legs 15v1 and 15v2
Are set so that their heights are slightly different.
That is, the driving side leg 15v1 is different from the non-driving side leg 15v2.
The height is set to be about 0.1 to 0.5 mm, and the drive side leg 15v1 is always in contact with the contact portion 2b1, but the non-drive side leg 15v2 is slightly floated from the contact portion 2b2. It is in a state. Therefore, in the normal cartridge mounting state, the process cartridge B has the shaft hole portion 15s, the shaft portion 16d,
And it is positioned at 3 places of the driving side leg 15v1,
Even if the entire process cartridge B receives a rotational moment in the clockwise direction during driving, the posture does not change. The non-driving side leg portion 15v2 abuts the abutting portion 2b2 and functions as a stopper when the process cartridge B is deformed by an external force such as vibration.

(Force Acting on Process Cartridge) When the process cartridge B is mounted and the upper opening / closing cover 1b is closed, the process cartridge B has, in addition to the downward urging force by the urging means 1b1 as described above, A force for urging the cartridge B upward also acts. In order to stabilize the process cartridge B in the mounted state, it is necessary to set the force for urging the cartridge B downward to be larger than the force for urging it upward.

<Upward force> The process cartridge B is biased upward by the electric contact pins 27a, 27b and 27c, the transfer roller 6 and the shutter mechanism 24.

When the process cartridge B is mounted, the electrical contact 18 exposed on the lower surface of the cartridge B
The electric contact pins 27a, 27b and 27c are pressed against the a, 18b and 18c, and the transfer roller 6 is pressed against the photosensitive drum 9. Therefore, as shown in FIG. 65 and FIG. 67, the cartridge B is biased upward by the forces F _c1 , F _c2 , and F _c3 by the springs 30 of the contact pins, and the spring 6 b of the transfer roller 6 (see FIG. It is urged upward by the force F _t by the reference (1). When the process cartridge B is mounted, the opened shutter mechanism 24 is constantly biased in the closing direction by the torsion coil spring 24f. This force F _d acts in the direction of pulling out the process cartridge B, and its vertical component F
_The process cartridge B is biased upward by _d1 and _Fd2 .

<Downward force> On the other hand, the downward urging of the process cartridge B is urged downward by the forces F _s1 , F _s2 by the urging means 1b1 and the force F _s3 by the leaf spring 1b2 as described above. It Further, the own weight of the cartridge B F _k1 , F _k2 , F
It is also urged downward by the rotation of the gear for transmitting the driving force to _k3 and the photosensitive drum 9.

That is, when the process cartridge B is mounted, as shown in FIG. 65, the drive for transmitting the driving force of the flange motor 9c attached to the longitudinal end of the photosensitive drum 9 and the drive motor provided in the main assembly A of the apparatus. The gear 31 meshes.
At this time, the direction of the meshing pressure angle between the two gears 9c and 31 is downward from the horizontal in the range of the angle θ = about 1 ° to 6 ° (about 4 ° in this embodiment). Therefore, at the time of image formation, the component force F _g1 of the meshing force F _g between the drive gear 31 and the flange gear 9c acts as a force for _urging the process cartridge B downward. This by the meshing force F _g gear downward from the horizontal as the process cartridge B is prevented from being pushed up.

If the meshing pressure angle is downward from the horizontal, the operator does not erroneously push the process cartridge B to the end (to the extent that the upper opening / closing cover 1b can be closed), closes the upper opening / closing cover 1b, and opens / closes the upper portion. Cover 1
When the closing of b is detected and the drive motor rotates, the process cartridge B is pulled in by the rotational force of the drive gear 31, the shaft hole portion 15s and the shaft portion 16d are fitted into the groove hole portion 2a1, and the process cartridge B Is completely set.

When the process cartridge B is mounted, if the process cartridge B is incompletely inserted so that the flange gear 9c and the drive gear 31 cannot mesh with each other, the process cartridge B is moved upward from the main assembly A of the apparatus. It protrudes and the upper opening / closing cover 1b cannot be closed.
Therefore, the operator notices that the mounting state of the process cartridge B is incomplete.

Even if the process cartridge B receives a force in the diagonally downward left direction in FIG. 65 due to the meshing pressure angle, the shaft hole portion 15s and the shaft portion 16d abut the groove hole portion 2a1. Cartridge B is stable. However, in the case where the meshing pressure angle is set obliquely downward from the horizontal as described above, when the process cartridge B is mounted, the flange gear 9c is driven by the drive gear 31c.
It will be an arrangement to overcome. Therefore, if the downward pressure angle is increased, the flange gear 9c may collide with the drive gear 31 when the process cartridge B is mounted. Also, when removing the process cartridge B, unless the cartridge B is largely lifted upward and then pulled out, there is a problem that the gears 9c and 31 collide with each other and it becomes difficult to disengage. Therefore, the downward pressure angle θ is preferably about 1 ° to 6 °.

(Relationship between Vertical Forces) As described above, in order to ensure that each contact pin comes into contact with the process cartridge B as the vertical force acting on the process cartridge B, the cartridge B is normally set. There must be. For that purpose, the following conditions must be met.

(1) A downward force is applied to the process cartridge B by the total pressure. (2) Drive side leg with the shaft hole 15s and the shaft 16d as shafts
15v1 does not float. (3) Shaft hole 15s and shaft with both legs 15v1 and 15v2 as shafts
16d does not float. (4) The drive-side shaft hole 15s and the drive-side leg 15v1 do not float around the non-drive-side shaft 16d and the non-drive-side leg 15v2. (5) The non-driving side shaft portion 16d and the non-driving side leg portion 15v2 do not float around the driving side shaft hole portion 15s and the driving side leg portion 15v1. (6) The drive-side shaft hole 15s does not float around the non-drive-side shaft 16d and the drive-side leg 15v1. (7) The non-driving side shaft portion 16d does not float around the driving side shaft hole portion 15s and the non-driving side leg portion 15v2.

However, in this case, since the leg portion 15v2 on the non-driving side is slightly floating from the contact portion 2b2, it is possible to eliminate the condition (7), and therefore (1) to (1)-
It suffices if the condition (6) is satisfied. Specifically, for example, in order to satisfy the condition (1), F _s1 + F _s2 + F _s3 + F _G1 + F _k1 + F _k2 + F _k3 > F _c1 + F
_It suffices to satisfy the relationship of _c2 + F _c3 + F _t + F _d1 + F _d2 .

To satisfy the condition (3), for example,
As shown in FIG. 68, it suffices that the rotational moment about the point p of the driving side leg 15v1 satisfies the following equation. However, M (T) in the following equation is a reaction force due to the torque of the cartridge B, and is a moment generated in the cartridge B in the clockwise direction around the point p in the figure. M (F _s1 + F _s2 ) + M (F _s3 ) + M (F _G1 ) + M (F _k1
+ F _k2 )> M (F _c1 ) + M (F _c2 ) + M (F _c3 ) + M
(F _t ) + M (F _d1 + F _d2 ) + M (T) (However, M (*) shown here indicates a moment)

Similarly, equations satisfying the above conditions (1) to (6) are obtained, and the pressing forces F _s1 , F _s2 and F _s3 are set so as to satisfy all of these conditional equations. As a result, the process cartridge B is stably fixed at a predetermined position inside the apparatus main body during image formation.

[Image Forming Operation] Next, the image forming operation of the image forming apparatus A in which the process cartridge B is mounted as described above will be described with reference to FIG.

When the apparatus inputs a recording start signal, the pickup roller 5a is driven and the conveying roller 5
b drives. As a result, the recording mediums are separated and fed one by one from the cassette 4 via the separation claws 4e, and the conveyance rollers 5
After being turned upside down along b, it is conveyed to the image forming unit while being guided by the guide 5c.

When a sensor (not shown) detects the front end of the recording medium, an image is formed in the image forming section in synchronization with the conveyance timing from the front end of the recording medium to the transfer nip portion.

That is, the photosensitive drum 9 rotates in the direction of the arrow in FIG. 1 in synchronism with the conveyance timing of the recording medium, and a charging bias is applied to the charging means 10 in accordance with this rotation to cause the surface of the photosensitive drum 9 to rotate. To evenly charge. Then, the optical system 3 irradiates the surface of the photosensitive drum 9 with laser light corresponding to the image signal, and forms a latent image on the surface of the drum according to the light irradiation.

Simultaneously with the formation of the latent image, the developing means 12 of the process cartridge B is driven and the toner feeding mechanism 12b is driven to feed the toner in the toner reservoir 12a to the developing sleeve 12d, and at the same time, the toner layer is formed on the rotating developing sleeve 12d. To form. The latent image on the photosensitive drum 9 is toner-developed by applying a voltage having the same polarity as the charging polarity of the photosensitive drum 9 and substantially the same potential to the developing sleeve 12d. Then, by applying a voltage having a polarity opposite to that of the toner to the transfer roller 6, the toner image on the photosensitive drum 9 is transferred onto the recording medium conveyed to the transfer nip portion.

The photosensitive drum 9 onto which the toner image has been transferred onto the recording medium further rotates in the direction of the arrow in FIG. 1, and the toner remaining on the photosensitive drum 9 is scraped off and removed by the cleaning blade 13a. Collect in reservoir 13c.

On the other hand, the recording medium on which the toner image has been transferred is conveyed to the fixing means 7 while being guided on the lower surface by the cover guide 5e. The fixing unit 7 applies heat and pressure to the recording medium to fix the toner image on the recording medium, and then the recording medium is curved by the relay discharge roller 5f and the sheet path 5g to correct the curl and reverse the front and back. Then, the sheet is discharged to the discharge section 8 by the discharge rollers 5h and 5i.

{Structure for removing process cartridge}
When a sensor (not shown) or the like detects that the toner in the developing unit is running low during the image formation as described above, the information is displayed on the display unit or the like of the apparatus main body A, and the operator replaces the process cartridge B. Call attention to. Hereinafter, a cartridge removal configuration when replacing the process cartridge B will be described.

To take out the process cartridge B from the apparatus main assembly A, first, as shown in FIG. 69, the upper opening / closing cover 1b is opened. At this time, since the biasing means 1b1 and the leaf spring 1b2 are separated from the process cartridge B together with the upper opening / closing cover 1b, the downward force acting on the cartridge B is the force F by the biasing means 1b1 and the leaf spring 1b2.
_{Since s1} + F _s2 + F _s3 is released, only the force F _k1 + F _k2 due to the own weight of the cartridge B becomes.

Here, the upward force F _c1 acting on the process cartridge B by the contact pins 27a, 27b, 27c.
+ F _c2 + F _c3 and the upward force F _t by the transfer roller 6 and the upward force F _d by the spring 24 f of the shutter mechanism 24 are
Downward force F _k1 + due to the weight of the process cartridge B
Since it is set to be slightly larger than F _k2 , when the upper opening / closing cover 1b is opened as described above, the process cartridge B floats slightly upward. Therefore, the meshing state between the flange gear 9c and the drive gear 31 is released, and the shaft hole portion 15s and the shaft portion 16d are disengaged from the groove hole portion 2a1. Thereby, even if the engagement pressure angle between the flange gear 9c and the drive gear 31 is lower than the horizontal direction, the process cartridge B can be smoothly pulled out.

On the other hand, in the conventional structure in which the process cartridge B is mounted on the upper opening / closing cover 1b, when the engagement pressure angle is lower than horizontal, the upper opening / closing cover 1b is opened. Flange gear 9
Since c and the drive gear 31 mesh with each other, the process cartridge B cannot be pulled out smoothly. Therefore, the drive gear 31 had to be provided with a one-way clutch or the like, but in this embodiment, when the upper opening cover 1b is opened, the engagement between the flange gear 9c and the drive gear 31 is automatically released. It is not necessary to provide a one-way clutch, etc., and the number of parts can be reduced.

Also, as described above, the process cartridge B
When the shaft hole portion 15s and the shaft portion 16d are disengaged from the groove hole portion 2a1, the process cartridge B is pulled out from the cartridge mounting portion 2 by the urging force of the spring 24f for closing the shutter mechanism 24 as described above. Be lifted to. Therefore, the process cartridge B can be taken out more easily.

The process cartridge B as described above
When the upper opening / closing cover 1b is opened, the transfer roller 6, the contact pins 27a, 27b, 27c, and the upward force of the shutter mechanism 24 slightly lift up in the removing direction.
It can be taken out smoothly and easily.

{Recycle Configuration of Process Cartridge} The process cartridge B removed as described above is recyclable. The recycling configuration will be described below. In order to protect the earth resources and the natural environment, the process cartridge B according to the present embodiment disassembles the upper and lower frames 14 and 15 when the toner in the toner reservoir 12a is used up, and stores the toner again in the toner reservoir 12a. And can be reused.

That is, the locking claw 14a and the locking opening 15 connecting the upper and lower frame bodies 14 and 15 shown in FIGS. 7 and 8, 37 and 38.
a, locking claw 14a and locking projection 15b, locking claw 14c and locking opening
The upper and lower frames 14 and 15 can be disassembled by releasing the locked state of the locking claw 15c, the locking opening 14b, and the locking claw 14e3 and the locking opening 15f3. This unlocking can be easily performed, for example, by setting the used process cartridge B in the disassembly tool 32, protruding the rod 32a and pushing the locking claw 14a as shown in FIG. In addition, each of the locking claws without using the disassembling tool 32
It can be disassembled by pressing 14a, 14c, 15c, 14e3.

After disassembling into the upper and lower frames 14 and 15 as shown in FIGS. 7 and 8 as described above, the waste toner adhering to the inside of the cartridge is removed by blowing air or the like for cleaning. At this time, since the photosensitive drum 9, the developing sleeve 12d, or the cleaning means 13 is a member that directly contacts the toner, a large amount of waste toner is attached. On the other hand, since the charging roller 10 is a member that does not come into direct contact with the toner, the amount of waste toner attached is small. Therefore, the cleaning of the charging roller 10 can be performed more easily than the cleaning of the photosensitive drum 9, the cleaning unit 13, etc., but in the present embodiment, the charging roller 10 includes the photosensitive drum 9 provided on the lower frame 15. , Developing sleeve 12
d. Since it is provided on the upper frame 14 which is separate from the cleaning means 13, the lower frame 15 and the divided upper frame 14 can be easily cleaned.

As shown in FIG. 60 (b), this disassembly line divides the upper and lower frame bodies 14 and 15 as described above to obtain the upper and lower frame bodies.
Each of the parts 14 and 15 is disassembled and cleaned, and the upper frame 14 includes the charging roller 10 and the like, and the lower frame 15 includes the photosensitive drum 9, the developing sleeve 12d, the developing blade 12e, the cleaning blade 13a, and the like. It will be easy to disassemble and clean to a level.

After cleaning the waste toner and the like, as shown in FIG. 58, a cover film 26 having a tear tape 25 is attached to the opening 12a2 to seal the opening 12a2, and the side surface of the toner reservoir 12a is closed. New toner is filled from the provided toner filling port 12a4 and the filling port 12a4 is covered with the lid 12a3. The upper and lower frames 14 and 15 are provided with the above-mentioned locking claws 14a and locking openings 15a, locking claws 14a and locking projections 15b, locking claws 14c and locking openings 15d, and locking claws 15c and locking openings. 14b, locking claw 14
The process cartridge B can be reused by locking the e3 and the locking opening 15f3 and connecting the two frames 14 and 15.

When the upper and lower frames 14 and 15 are reconnected, the locking claws 14a and the locking openings 15a, the locking claws 14a and the locking projections are formed.
Although 15b and the like are locked, it is conceivable that when the number of times the process cartridge B is reused increases, the locking between the locking claw and the locking opening becomes difficult. For this reason, in the present embodiment, screw holes that enable screwing are provided in the vicinity of the respective locking claws and locking openings, or at locations where the locking claws and the like exhibit the same effect as the locking force. For example, screw holes 14a1 are provided in the vicinity of the locking claws 14a of the developing means 12 disposed in the upper frame 14, and the locking openings 15a on the side of the lower frame 15 corresponding to the screw holes 14a1. Screw holes 15a1 are provided near the respective positions. In addition to this, a fitting convex portion 14d and a fitting concave portion 15e (cleaning means side), fitting convex portions 15f1 and 14e2 and fitting concave portions 14e1 and 15f2 (developing means side) are provided near the four corners of the frame. And screw holes are formed through them. As a result, even if the locking by the locking claws becomes difficult, the upper and lower frame bodies 14 and 15 can be coupled to each other and the screws can be screwed into the screw holes to firmly couple the both frame bodies 14 and 15. Becomes

[Other Embodiments] Next, other embodiments of the respective parts of the image forming apparatus and the process cartridge described above will be described with reference to the drawings. The parts having the same functions as those in the first embodiment described above are designated by the same reference numerals.

(Image Carrier) In the above-described first embodiment, an example in which an organic semiconductor (OPC) is used as the photosensitive layer of the image carrier is shown, but the invention is not limited to this and, for example, amorphous silicon. (A-Si), selenium (S
e), zinc oxide (ZnO), or cadmium sulfide (C
It may be dS) or the like.

<Flange Gear> In the above-described first embodiment, as a means for preventing the deformation of the flange gear 9c due to the load at the time of transmitting the driving force, as shown in FIG. 9, the lightening portion 9c3 of the flange gear 9c is formed. Although the example in which the reinforcing material 9c4 is press-fitted is shown in the above, the present invention is not limited to this, and it is sufficient if the flange gear alone can satisfy the strength by adding ribs or the like without press-fitting the reinforcing material 9c4. For example, the flange gear having the configuration shown in FIG. 71 is that.

Since the flange gear 9c is a plastic material formed by injection molding, the inside of the bottom of the gear portion is lightened, as described above. However, as shown in FIG. 9, a rib is formed in the lightening portion 9c3. If the flange gear 9c is provided, the gear accuracy may be deteriorated if it is provided. Therefore, as shown in FIG. 71, the flange gear 9c according to the present embodiment has a thinned-out portion 9c3 and a wall portion 9c6 with a gear portion. The ribs 9c7 are formed so as to be located at the tooth bottom of the same, and at the same time, a large number of ribs 9c7 are formed in the lightening portion 9c3. Thereby, the strength can be increased without deteriorating the gear accuracy.

<Drum Support Shaft> In the above-described first embodiment, the end surface of the drum support shaft 9d is used as a means for facilitating disassembly of the drum support shaft 9d press-fitted into the shaft hole 15s of the lower frame 15. Although the example in which the screw hole 9d1 is provided is shown in the above, the present embodiment is not limited to this, and any structure may be used as long as the press-fitted drum support shaft 9d can be easily extracted.

For example, as shown in FIG. 72 (a), a cutout 9d2 may be provided in a part of the drum support shaft 9d and the shaft hole 15s of the lower frame body 15, or as shown in FIG. 72 (b), a lower frame may be formed. the flange portion of the drum axle 9d than the outer diameter R _a shaft hole portion 15s of the body 15 9
If the outer diameter _{Rb of} d3 is increased, the drum support shaft 9d can be easily pulled out. Further, in the present embodiment, the cost of cutting the screw can be omitted, and the manufacturing cost can be suppressed.

(Charging Means) <Sliding Bearing> In the above-mentioned first embodiment, as a thrust regulating means for regulating the thrust direction force of the charging roller 10,
As shown in FIGS. 18 and 19, an example is shown in which the sliding bearing 10c is integrally formed with the stopper portion 10c1 that is bent in a hook shape. However, the present invention is not limited to this, and the thrust regulating portion is integrally formed with the sliding bearing. It should be formed.

For example, as shown in FIG. 73 (a), a sliding bearing
The stopper part 10 is provided with a wall integrally provided on the entire one end surface of 10c.
74a, a convex rib 10c2 is provided on the inner surface of the stopper portion 10c1 to increase the frictional resistance when the roller shaft end portion of the charging roller 10 rotates in contact with the stopper portion 10c1. You may make it reduce. Also, the sliding bearing 10c
It is not necessary for the wall provided integrally with the
As shown in FIG. 73 (b) and FIG. 74 (b), a part of the end of the charging roller 10 is regulated to reduce frictional resistance when the end of the charging roller 10 comes into contact and rotates. You may do it.

In the above-described embodiment, the sliding bearing 10c rotatably supporting the charging roller 10 is integrally provided with the stopper portion 10c1 as the thrust regulating means. However, the present invention is not limited to this. However, the same effect can be obtained by using it for a transfer roller or the like.

Further, the charging means has a so-called contact charging method used in the above-mentioned first embodiment, but a tungsten wire which has been conventionally used as another structure is provided with a metal shield such as aluminum around three sides. It goes without saying that a configuration may be used in which positive or negative ions generated by applying a high voltage to the tungsten wire are moved to the surface of the photoconductor drum to uniformly charge the drum surface.

As the contact charging means, in addition to the roller type, a blade type (charging blade), a pad type,
Block type, rod type, wire type and the like may be used.

(Developing Means) As the developing method, various known developing methods such as a two-component magnetic brush developing method, a cascade developing method, a touch-down developing method and a cloud developing method can be used.

(Cleaning Means) <Cleaning Blade> In the first embodiment described above, as a means for suppressing noise due to vibration of the cleaning blade 13a, as shown in FIGS. 31 and 32, a predetermined position inside the upper frame 14 is provided. the rib 14j is provided, but this was through a seal member S ₁ constructed as abutted on the upper surface of the blade supporting member 13a1, the present invention is not limited thereto, as long as the stifle vibration of the blade 13a For example, it may be made to abut against the inclined surface of the support member 13a1 fixing the blade 13a.

As shown in FIG. 75, a cushioning material 33 such as chloroprene rubber may be sandwiched between the upper frame 14 and the support member 13a1 to which the cleaning blade 13a is fixed. A seal member S ₁ is provided beside the cushioning material 33 to prevent the waste toner from leaking. The cushioning material 33 has a thickness of about 0. from the gap between the upper surface of the support member 13a1 and the inner surface of the upper frame body 14.
About 5 to 1.5 mm thick and the length in the longitudinal direction is about 150 to 220
The thickness of about 0.1 mm is used, and the upper frame body 14 is bent by about 0.5 mm to 1.0 mm by sandwiching the cushioning member 33. That is, the cleaning blade with a force of the amount that the upper frame 14 is bent.
The fixed support member 13a1 of 13a is pressed. As a result, vibration caused by stick-slip of the cleaning blade 13a is suppressed and noise generated from the process cartridge is reduced.

Further, as shown in FIG. 76, the cushioning material 33 may be arranged between the rib 14j of the upper frame 14 and the blade supporting member 13a1. The cushioning material 33 in this embodiment is made of urethane rubber having a thickness of 0.5 mm or less, and has a thickness of about 0.3 mm and a hardness of about 60 ° between the rib 14j and the blade supporting member 13a1 when the cartridge is assembled. It is crushed to become. As a result, it is possible to suppress minute vibrations of several tens of Hz or more due to stick slip of the cleaning blade 13a, and to prevent noise from being generated.
In addition, a good image could be obtained.

Further, as shown in FIGS. 77 and 78, the upper frame 14
A rib 14j provided at a predetermined position of the blade supporting member 13
You may make it contact a1 directly. The rib 14j as shown in FIG. 77 contacts almost the entire upper surface of the blade supporting member 13a1, and the rib 14j as shown in FIG. 78 contacts substantially the entire area (upper surface and inclined surface) of the blade supporting member 13a1. This increases the vibration transmissibility of the cleaning blade 13a to the cartridge frame through the rib 14j, but the mass of the vibrating object itself (mass of the cartridge frame) increases, so that the vibration of the cleaning blade 13a is caused by the cartridge frame. The vibration of the blade 13a can be reduced, and noise due to the vibration can be reduced.

Further, as shown in FIG. 79, the portion of the upper frame 14 where the cleaning blade 13a is close (the rib 14 is
j) was provided in the opening) over the longitudinal direction.
34 is provided, and the blade supporting member is inserted into the predetermined position of the upper opening / closing cover 1b on the apparatus main body side through the opening 34.
A contact member 35 that contacts the upper surface of 13a1 may be provided, and the contact member 35 may contact the upper surface of the blade support member 13a1 by closing the upper opening / closing cover 1b.
As a result, the vibration of the cleaning blade 13a is transmitted to the entire apparatus through the contact member 35, but the mass of the vibrating object itself (mass of the entire apparatus) is further increased, so that the vibration of the cleaning blade 13a is dispersed throughout the apparatus. Is
Vibration of the blade 13a can be reduced, and noise due to the vibration can be reduced. The blade support member 13
A thin, flexible cushioning material such as a rubber sheet may be interposed between a and the abutting member 35 to improve the adhesion.

As shown in FIG. 80, the blade support member
When the 13a1 is screwed and fixed to the cartridge frame, not only the longitudinal ends of the inclined surface but also the longitudinal ends of the upper surface may be screwed and fixed. As a result, similar to the above-described embodiment, it is possible to suppress microvibration of several tens of Hz or more generated due to the frictional force between the photosensitive drum 9 and the cleaning blade 13a, noise is eliminated, and a good image is obtained. I was able to.

Incidentally, as shown in FIG. 81, the cleaning means 13
In the case of a single unit, the same effect as in the above embodiment can be obtained by screwing and fixing the central portion of the upper surface of the blade supporting member 13a1.

Further, as shown in FIG. 82, a rib slightly taller than the gap between the inner surface of the upper frame 14 and the upper surface of the blade supporting member 13a1.
14j is provided in the central portion in the longitudinal direction of the inner surface of the upper frame body 14,
Using the elastic deformation of the upper frame 14 when the rib 14j is pressed against the blade support member 13a1, the blade support member
You may comprise so that the upper surface of 13a1 may be pressurized. As a result, the rib 14j is pressed against the upper surface of the blade supporting member 13a1 by the elastic deformation of the upper frame body 14, so that the vibration of the cleaning blade 13a can be suppressed by this pressing force, and the noise due to the vibration is reduced. .

Further, as shown in FIG. 83, a partition plate which is slightly taller than the distance between the bottom of the waste toner reservoir 13c and the upper portion of the blade supporting member 13a1 is provided in the central portion of the lower frame 15 in the waste toner reservoir 13c in the longitudinal direction. Even if 36 is provided, the same effect as that of the above-described embodiment can be obtained. By providing this partition plate 36, the strength of the lower frame body 15 is also improved.

By carrying out this embodiment as described above, it is possible to suppress a slight vibration of several tens Hz or more generated by the frictional force between the photosensitive drum 9 and the cleaning blade 13a. The amplitudes of the photosensitive drum 9 and the cleaning blade 13a before carrying out this embodiment are about 4 μm to 5 μm, respectively.
By contrast, the measurement error was 0.01 μm or less, and the noise due to the vibration was eliminated, and a good image could be obtained.

As a method of cleaning the toner remaining on the photosensitive drum 9, the cleaning means may be constituted by using a blade, a fur brush, a magnetic brush or the like.

(Upper and Lower Frame) In the above-described first embodiment, the developing-side driving portion of the lower frame 15 is formed into a substantially box shape, and further ribs or the like are provided to increase the partial strength of the frame. However, it is also possible to increase the strength of the other parts of the upper and lower frames 14 and 15 by using the method described in the above embodiment.

(Shutter Mechanism) In the above-described first embodiment, when the process cartridge B is mounted, the shutter mechanism 24 automatically opens, and when the cartridge B is pulled out, the shutter mechanism 24 is automatically twisted by the torsion coil spring 24f. I tried to close it. Therefore, when the process cartridge B is mounted, the shutter mechanism 24 is
There is an advantage that the cartridge B is always urged in the closing direction by f, and thus the cartridge B is urged in the direction to be lifted from the cartridge mounting portion 2 inside the apparatus main body. But,
If the biasing force of the torsion coil spring 24f is too strong, the cartridge mounting state becomes unstable. Therefore, a lock mechanism for locking the shutter mechanism 24 when it is opened may be provided.

As the lock mechanism, for example, as shown in FIG. 84, a lever 39b urged by a compression spring 39a is provided at a predetermined position of the cartridge B, and when the shutter mechanism 24 is completely opened, the lever 39b causes the shutter portion. It is configured to be locked in a locking hole 24c2 provided in 24c. As a result, the shutter mechanism 24 is locked in the open state, and the biasing force of the torsion coil spring 24f does not act to lift the process cartridge B.

The lock state is released by the eject button 40 shown in FIG. That is, the eject button 40 is attached to the apparatus body so as to be exposed,
It is urged by a compression spring 40c in a direction projecting to the outside of the apparatus main body. When this eject button 40 is pressed, the pressing protrusion 40a at the tip of the button pushes the lever 39b,
The lever 39b is disengaged from the locking hole 24c2. As a result, the locked state is released.

The eject button 40 has a locking claw 40b, which locks the upper opening / closing cover 1b when the upper opening / closing cover 1b is closed by locking the locking hook 41 provided on the cover 1b. Lock it. Meanwhile, the eject button
When 40 is pressed, the locking is released, and the opening / closing cover 1b is opened by the urging of a torsion coil spring provided at the center of rotation of the upper opening / closing cover 1b. Therefore, when the eject button 40 is pressed, the upper opening / closing cover 1b is automatically opened, and the process cartridge B is lifted up from the cartridge mounting portion 2 by the urging force of the spring 24f, so that the process cartridge B can be easily taken out. is there.

Further, the biasing by the drum shutter can be carried out with a configuration which is completely different from that of the above-mentioned first embodiment, as shown in FIGS. 85 to 89. Next, the configuration of the embodiment shown in FIGS. 85 to 89 will be described.

In this embodiment, the process cartridge 42 shown in FIG. 85 is inserted through the cartridge insertion window 44 provided on the front surface of the image forming apparatus 43 and mounted. The process cartridge 42 and the image forming apparatus 43 have the same functions as the process cartridge B and the image forming apparatus A of the first embodiment described above. The process cartridge 42 includes a cartridge body 42a and a case 42b that functions as a shutter mechanism.

As shown in FIG. 86, the cartridge insertion window 44 is closed by a thin plate 46 which is urged in a closing direction by a spring 45, and the process cartridge 42 is inserted by pushing the thin plate 46 open. As shown in FIG. 87, the eaves portion 42c is inserted until it becomes substantially flush with the front surface of the image forming apparatus main body. When the cartridge main body 42a is further pushed in from this state, the case 42b remains in the same position and the main body 42a is pushed out. Then, the sensor (not shown) detects the protrusion of the cartridge main body 42a, and the gear 47 connected to the motor (not shown) rotates.

The gear 47 can mesh with the rack 42a1 provided on the upper surface of the cartridge body 42a, and the rotation of the gear 47 causes the cartridge body 42a to be further extended from the case 42b. At this time, a shaft 48 coaxial with the rotation shaft of the photosensitive drum provided in the cartridge main body enters a guide groove 49 in the image forming apparatus 43, and is guided into this groove 49 and fed out. As shown in FIG. 88, a contact 50 for electrical connection is provided at the rear of the cartridge main body 42a (on the left side of FIG. 88), and when the cartridge main body 42a is extended, the contact 50 is provided. It is provided on the side and the spring
It contacts the contact pin 52 which is urged downward by 51. At this time, the cartridge body 42a is urged by the urging of the contact pin 52.
Receives a downward force, and the rear of the cartridge main body 42a slightly descends along the guide groove 49.

When the cartridge main body 42a is inserted, the shaft 53 provided on the image forming apparatus 43 is attached to the hole 42b1 of the case 42b.
Fall into. The shaft 53 is biased by a compression spring 55 via a lever 54 in a direction in which the shaft 53 falls into the hole 42b1, and the lever 54 projects from the outside of the image forming apparatus 43. Then, when the cartridge body 42a is extended and reaches a predetermined position, the shaft 53 is provided with a recess 42 provided on the side surface of the cartridge body.
Depress to a2. Therefore, the cartridge main body 42a is locked against the bias of the tension spring 42d that tries to pull it into the case 42b. Therefore, in this locked state, the force of the tension spring 42d that tries to move the cartridge main body 42a from the normal position does not act, and the process cartridge 42 is stably attached to the image forming apparatus 43.

The lever 54 is rotatable about the shaft 54a. When a force is applied in the direction of the arrow in FIG. 89, the shaft 53 is pulled out from the recess 42a2 by the urging of the tension spring 42d, and the cartridge body 42a is moved to the case 42b. Is pulled back in. Since the gear 47 and the rack 42a1 mesh with each other during the pullback, the gear 47 serves as a damper to prevent the cartridge main body 42a from being pulled back to the case 42b by shock.

When the cartridge body 42a is pulled back into the case 42b, as shown in FIG.
Since a protrudes from the image forming apparatus 43 by a certain amount, it can be easily taken out.

[0277] In this way, the cartridge main body 42a is made into a case.
While sufficiently strengthening the tension spring 42d that pulls back to 42b,
By providing the lock mechanism, the cartridge 42 can be taken out very easily.

Further, in this structure, as shown in FIG. 90, the mounting state of the cartridge 42 can be determined by the state of the lever 54. That is, when the process cartridge 42 is not attached to the image forming apparatus 43, the lever 54 is moved to the position shown in FIG.
In the state of (a), when the process cartridge 42 is properly mounted and the shaft 53 is recessed in the recess 42a2, FIG.
In the state of (b), the cartridge 42 is set in the image forming apparatus 43.
When it is not properly attached to, the state is as shown in FIG. 90 (c). In this way, the cartridge mounting state can be determined only by looking at the state of the lever 54 from the outside of the image forming apparatus.

{Assembly Structure of Process Cartridge} <Cleaning Blade End Seal> In the above-described first embodiment, the seal member S ₆ attached to the lower portion of the blade mounting seat surface 15j corresponding to the end of the cleaning blade 13a for preventing toner leakage. As a means for reducing the frictional force between the photosensitive drum 9 and the end of the photosensitive drum 9, as shown in FIG.
₆ shows an example in which a high-density polyethylene seal 37 is pasted on or a lubricant 38 such as silicon fine powder is applied as shown in FIG. 51, but the present invention is not limited to this, and the lubricant A powder such as polyvinylidene fluoride (PVDF) may be used as 38.

Here, as a method of adhering the lubricant 38, which is the powder, to the seal member S ₆ , it is sufficient to sprinkle the lubricant 38 on the seal member S ₆ . This is because when the frictional force between the seal member S ₆ and the end of the photosensitive drum 9 is not relatively large, the surface of the seal member S ₆ is rough and the frictional force is large at the initial stage of rotation of the drum 9. On the other hand, after a certain amount of time has passed, the surface roughness of the seal member S ₆ is reduced and the frictional force is also reduced.

Further, the lubricant 38, which is the powder, is dispersed in a volatile liquid, the solution is impregnated into the sealing member S ₆ , and the liquid 38 is evaporated to disperse the lubricant 38 in the entire seal. May be. By doing so, the lubricant 38 dispersed inside the seal gradually appears on the contact surface with the photoconductor drum 9, and the frictional force with the drum 9 is reduced for a long period of time, and due to the winding of the drum 9. Seal member S
₆ tears can be prevented.

<Mounting Method of Photoreceptor Drum> In the above-described first embodiment, in order to interpose the lubricant 38 on the entire contact surface between the photoreceptor drum 9 and the cleaning blade 13a at the time of initial assembly of the cartridge, the contact of the blade 13a is made. The method of mounting the drum 9 at an angle γ of 45 degrees or less with respect to the contact surface has been described, and this drum mounting method may be used for assembling the cartridge at the time of recycling.

Assuming that the parts used in the process cartridge have different endurance performances, the photosensitive drum 9 is more durable than the cleaning blade 13a.
When considering the case where the durability is poor, this process cartridge can be reused by replacing only the photosensitive drum 9 with a new one. This photoconductor drum 9
When the drum 9 is removed when replacing the blade
The residual developer adheres to the contact surface of the drum 13a with the drum 9, and the residual developer can serve as the lubricant 38 described above. However, since the residual developer is generally dispersed and adhered to both the drum 9 and the blade 13a,
It does not adhere in a state in which it covers the entire contact surface with the drum 9 on 13a.

Therefore, by using the drum mounting method of the present invention, the residual developer existing on the blade 13a when the new photosensitive drum 9 is remounted to the process cartridge B is transferred to the photosensitive drum 9 of the blade 13a. Can be dispersed over the entire contact surface, and the residual developer can be interposed as a lubricant between the both members.

Further, the process cartridge according to the present invention is not limited to the case of forming a monochromatic image as described above, but a plurality of developing means 12 are provided and a multicolor image (for example, a two color image,
It can also be suitably applied to a cartridge that forms a three-color image or full-color image.

The above-mentioned process cartridge B is provided with, for example, an electrophotographic photosensitive member as an image carrier and at least one of process means. Therefore, as the mode of the process cartridge, in addition to the embodiment described above, for example, the image carrier and the charging means are integrally made into a cartridge, which can be attached to and detached from the apparatus main body. The image carrier and the developing means are integrally formed into a cartridge, which can be attached to and detached from the main body of the apparatus. The image carrier and the cleaning means are integrally made into a cartridge so that it can be attached to and detached from the apparatus main body. Further, there is one in which an image carrier and two or more of the above-mentioned process means are combined into an integrated cartridge, which can be attached to and detached from the apparatus main body.

That is, the above-mentioned process cartridge is a cartridge in which the charging means, the developing means or the cleaning means and the electrophotographic photosensitive member are integrally formed, and the cartridge can be attached to and detached from the main body of the image forming apparatus. Further, at least one of the charging means, the developing means, and the cleaning means and the electrophotographic photosensitive member are integrally made into a cartridge so that it can be attached to and detached from the main body of the image forming apparatus.
Further, it means that at least the developing means and the electrophotographic photosensitive member are integrally made into a cartridge so as to be attachable to and detachable from the main body of the image forming apparatus.

Further, although the laser beam printer has been illustrated as the image forming apparatus in the above-mentioned embodiments, the present invention is not limited to this, and other examples such as an electrophotographic copying machine, a facsimile machine, an LED printer, or a word processor can be used. Of course, it can be used in an image forming apparatus.

[0289]

As described above, according to the present invention, even when the photosensitive drum is displaced in the direction away from the charging roller during driving, the displacement amount is different between the driving side and the non-driving side. However, since the allowable movement amount of the charging roller is set sufficiently on each side, charging failure will not occur,
In addition, the charging roller can be surely brought into close contact with the photosensitive drum and stable charging can be performed without inviting adverse effects such as an increase in size of the process cartridge and an increase in cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration explanatory diagram of a laser printer equipped with a process cartridge that is one mode of an image forming apparatus.

FIG. 2 is an external perspective view of the laser printer.

FIG. 3 is a cross-sectional configuration diagram of the process cartridge.

FIG. 4 is an external perspective view of the process cartridge.

FIG. 5 is an external perspective view of the process cartridge in an inverted state.

FIG. 6 is a cross-sectional explanatory view of the process cartridge with the upper and lower frame bodies divided.

FIG. 7 is an internal perspective explanatory diagram on the lower frame side.

FIG. 8 is an internal perspective explanatory view on the upper frame side.

FIG. 9 is a cross-sectional explanatory diagram of a photosensitive drum.

FIG. 10 is an explanatory diagram of a flange gear portion at the end of the photosensitive drum.

FIG. 11 is a perspective view illustrating a drum ground contact.

FIG. 12 is a perspective explanatory view of a contact for drum ground.

FIG. 13 is a cross-sectional explanatory view of an example using a drum ground that is not bifurcated.

FIG. 14 is a cross-sectional explanatory view of an example using a drum ground that is not bifurcated.

FIG. 15 is an explanatory view of a main part showing an enlarged vicinity of a drum shaft.

FIG. 16 is an explanatory diagram of a work of extracting the drum shaft from the frame body.

FIG. 17 is a main part explanatory view showing a charging roller portion in an enlarged manner.

FIG. 18 is a principal part explanatory view showing an enlarged charging roller portion.

FIG. 19 is a perspective explanatory view of a bearing of the charging roller.

20 is a cross-sectional view taken along the line AA in FIG. 3.

21 is a sectional view taken along line BB in FIG. 20.

FIG. 22 is a lateral cross-sectional explanatory view showing a positional relationship between a photosensitive drum and a developing sleeve and a method of pressing the developing sleeve.

23 is a vertical cross-sectional view showing the AA-AA cross section of FIG. 22, and FIG.
FIG. 22 is a vertical sectional view showing a BB-BB section of 22.

FIG. 24 is an explanatory sectional view showing a sliding state of a conventional sleeve bearing.

FIG. 25 is an explanatory diagram showing a combined state of the developing sleeve and the sleeve gear.

FIG. 26 is an explanatory diagram showing undulations of a squishy sheet.

FIG. 27 is an explanatory diagram showing a method of attaching a squi sheet.

FIG. 28 is an explanatory diagram showing a method of attaching a squi sheet.

FIG. 29 is an explanatory view showing the shape of a squishy sheet.

FIG. 30 is an explanatory diagram showing a method of attaching a squi sheet.

FIG. 31 is an explanatory cross-sectional view showing a contact state between a cleaning blade support member and a rib provided on the upper frame.

FIG. 32 is a front explanatory view showing a contact state between a cleaning blade supporting member and a rib provided on the upper frame.

FIG. 33 is a normal distribution diagram of the average particle diameter of toner.

FIG. 34 is an explanatory diagram of a blade penetration amount and a blade setting angle.

FIG. 35 is an explanatory diagram of a method for measuring a blade contact pressure.

FIG. 36 is a table showing the relationship between blade contact pressure and toner average particle diameter.

FIG. 37 is an internal plan view of the lower frame body side.

FIG. 38 is an internal plan view of the upper frame side.

FIG. 39 is an explanatory diagram of guiding the recording medium on the lower surface of the lower frame.

FIG. 40 is a perspective explanatory view of a shutter mechanism.

FIG. 41 is an external side view of the process cartridge.

FIG. 42 is an external bottom view of the process cartridge.

43 is a perspective explanatory view of a shutter shaft retainer. FIG.

FIG. 44 is an external top surface explanatory diagram of the process cartridge.

FIG. 45 is an explanatory diagram of a state in which the photosensitive drum is incorporated last.

FIG. 46 is an explanatory diagram showing a toner adhesion state at an end portion of the developing sleeve.

FIG. 47 is an explanatory diagram showing a molded state of the developing sleeve mounting seat surface.

FIG. 48 is an explanatory diagram of an example in which a developing blade and a cleaning blade are attached.

FIG. 49 is an explanatory diagram showing a state of a seal member at an end portion of a cleaning blade.

FIG. 50 is a state explanatory view showing the relationship between the seal member at the end of the cleaning blade and the photosensitive drum.

FIG. 51 is an explanatory diagram showing a state of the lubricant applied to the cleaning blade and the end seal member.

FIG. 52 is an explanatory diagram showing a state of the seal member at the end portion of the developing blade.

FIG. 53 is an explanatory diagram of the shape of the seal member at the end of the developing blade.

FIG. 54 is an explanatory diagram showing a mounting position of the guide member when the photosensitive drum is incorporated.

FIG. 55 is a configuration explanatory view in which a drum guide member is provided at an end portion of a blade support member.

FIG. 56 is a schematic explanatory diagram showing a state of the lubricant on the contact surface of the cleaning blade with the photosensitive drum.

FIG. 57 is an explanatory diagram of how the bearing members of the photosensitive drum and the developing sleeve are attached.

FIG. 58 is an explanatory diagram showing a state where a cover film having a tear tape is attached to a toner reservoir opening.

FIG. 59 is an explanatory diagram showing a state of a seal member attached to a portion where a tear tape is pulled out.

FIG. 60A is an explanatory diagram of a process cartridge assembly and shipping line, and FIG. 60B is an explanatory diagram of a process cartridge disassembly cleaning line.

FIG. 61 is an explanatory diagram of a state in which the process cartridge is attached to the image forming apparatus.

FIG. 62 is a diagram illustrating a state in which the process cartridge is attached to the image forming apparatus.

FIG. 63 is an explanatory diagram of a state in which the process cartridge is attached to the image forming apparatus.

FIG. 64 is an explanatory diagram of a state in which the process cartridge is attached to the image forming apparatus.

FIG. 65 is an explanatory diagram of a state in which the process cartridge is attached to the image forming apparatus.

FIG. 66 is an explanatory diagram of gears and electric contacts attached to the photosensitive drum.

FIG. 67 is an explanatory diagram of a force applied to the process cartridge.

FIG. 68 is an explanatory view of a state of a rotation moment around the protrusion on the drive side of the process cartridge.

FIG. 69 is an explanatory view of the state of the process cartridge when the upper opening cover is opened.

[FIG. 70] FIG. 70 is an explanatory diagram of a case where the connection between the upper frame body and the lower frame body is released.

FIG. 71 is an explanatory diagram of another example of the flange gear portion at the end of the photosensitive drum.

FIG. 72 is an explanatory diagram of another embodiment of the drum support shaft according to the present invention.

FIG. 73 is an explanatory diagram of another embodiment of the sliding bearing according to the present invention.

FIG. 74 is an explanatory diagram of another example of the sliding bearing according to the present invention.

FIG. 75 is an explanatory diagram of another embodiment of the cleaning means according to the present invention.

FIG. 76 is an explanatory diagram of another embodiment of the cleaning means according to the present invention.

FIG. 77 is an explanatory diagram of another embodiment of the cleaning means according to the present invention.

FIG. 78 is an explanatory diagram of another embodiment of the cleaning means according to the present invention.

FIG. 79 is an explanatory diagram of another embodiment of the cleaning unit according to the present invention.

FIG. 80 is an illustration of another embodiment of the cleaning means according to the present invention.

FIG. 81 is an explanatory view of another embodiment of the cleaning means according to the present invention.

FIG. 82 is an illustration of another embodiment of the cleaning means according to the present invention.

FIG. 83 is an explanatory diagram of another embodiment of the cleaning means according to the present invention.

84 is an explanatory diagram of another example in which a lock mechanism that locks the shutter mechanism in the opened state is provided. FIG.

FIG. 85 is a perspective explanatory diagram of an image forming apparatus and a process cartridge according to another embodiment of the biasing structure of the shutter mechanism.

FIG. 86 is a configuration explanatory diagram of an image forming apparatus and a process cartridge according to another embodiment of the biasing configuration of the shutter mechanism.

FIG. 87 is another example of the biasing structure by the shutter mechanism, and is an explanatory view of an initial state in which the cartridge is inserted into the image forming apparatus.

88 is another embodiment of the biasing structure by the shutter mechanism, and is an explanatory view of a state where the cartridge main body is extended from the case. FIG.

FIG. 89 is a structural explanatory view of a lock lever, which is another embodiment of the biasing structure by the shutter mechanism.

FIG. 90 is an explanatory view showing the state of the lock lever, which is another embodiment of the biasing structure by the shutter mechanism.

[Explanation of symbols]

A ... Image forming apparatus B ... Process cartridge S ₁ ,
_{S 2, S 3, S 4} , S 5, S 6 ... sealing member S ₇ ... sealing member S ₇₁ ... upper portion S ₇₂ ... lower portion S _8, S ₉ ...
Seal member Z ... Photoreceptor coating area 1 ... Device body 1a
... Cassette mounting portion 1b ... Upper opening / closing cover 1b1 ... Energizing means 1b2 ... Leaf spring 1b3 ... Arm portion 1b4 ... Rotating shaft 2 ... Cartridge mounting portion 2a ... First guide portion 2a1 ... Groove hole portion 2b ... Second guide portion 2b1 , 2b2 ... Contact portion 2c ... Shutter cam surface 3 ... Optical system 3a ... Laser diode 3b ... Polygon mirror 3
c ... Scanner motor 3d ... Imaging lens 3e ... Scanner unit 3f ...
Reflective mirror 3g ... Laser shutter 4 ... Cassette
4a ... Handle part 4b ... Shaft 4c ... Stacking plate 4d ... Spring
4e ... Separation claw 5 ... Recording medium conveying means 5a ... Pickup roller 5b ... Inversion roller 5c ... Guide 5d ...
Roller 5e ... Cover guide 5f ... Relay transport roller 5
g ... Second reversal sheet path 5h, 5i ... Ejection roller 6
... transfer means 6a ... bearing 6b ... spring 6c ... guide member 6d ... shaft 7 ... fixing means 7a ... film guide member 7b ... ceramic heater 7c ... thin film 7
d ... Pressure roller 7f ... Inlet side guide 7g ... Outlet side guide 8 ... Ejection section 9 ... Photosensitive drum 9a ... Conductive substrate 9a1 ... End surface part 9b ... Organic semiconductor 9c ... Flange gear 9c1 ... Helical gear 9c2 ... Spur tooth gear 9c3 ... Lightening portion 9c4 ... Reinforcing material 9c5 ... Groove portion 9c6 ... Wall 9c7 ...
Rib 9d ... Drum support shaft 9d1 ... Screw hole 9d2 ... Notch
9d3 ... Flange portion 9d4 ... Support portion 10 ... Charging means 10a
… Spring 10b… Roller shaft 10c… Sliding bearing 10c1… Stopper part
10c2 ... Rib 10c3 ... Receiving surface 11 ... Exposure means 11a ... Opening 12 ... Developing means 12a ... Toner reservoir 12a1 ... U-shaped groove
12a2 ... Opening 12a3 ... Lid 12a4 ... Filling port 12b ... Toner feeding mechanism 12b1 ... Feeding member 12b2 ... Arm member 12b3 ...
Shaft 12b4 ... Locking protrusion 12b5 ... Slot 12c ... Magnet 12d ...
Developing sleeve 12d1 ... Contact ring 12d2 ... Gate
12e ... Development blade 12e1 ... Support member 12e2 ... Screw 12
e3 ... Reinforcing member 12e4 ... Adhesive 12e5 ... Projection 12f ... Lid member 12f1 ... Hanging member 12f2 ... Rib 12f3 ... Swelling part
12f4 ... Groove 12g ... Sleeve gear 12g1 ... Boss 12g2
… Mating holes 12h, 12i… Sleeve bearings 12i1… Retaining protrusions 12j… Pressing springs 12k… Sleeve flanges 12k1, 12k2… Steps 12k3… Mating parts 12k4… Projections
12k5 ... Recess 13 ... Cleaning means 13a ... Cleaning blade 13a1 ... Support member 13a2 ... Screw 13a3 ... Adhesive 13a4 ... Projection 13b ... Squisheet 13
c ... Waste toner reservoir 13c1 ... Partition plate 13d ... Mounting surface 13d1 ...
Lower end both sides 13e ... Double-sided tape 13f ... Lower end position 14 ... Upper frame 14a ... Locking claw 14a1 ... Screw hole 14b ... Locking opening 14
c ... Locking claw 14d ... Fitting convex portion 14e1 ... Fitting concave portion 14e2 ...
Fitting convex part 14e3 ... Locking claw 14f ... Opening part 14g ... Through hole 14h ... Fitting convex part 14i ... Concave guide 14
j ... rib 14k ... supporting part 14m ... groove 14n ... bearing slide guide claw 14p ... drooping member 14q ... first engaging part 14r ... second engaging part 15 ... lower frame 15a ... locking opening 15a1
… Screw hole 15b… Locking projection 15c… Locking claw 15d… Locking opening 15e… Mating recess 15f1… Mating projection 15f2… Mating recess 15f3… Locking opening 15g… Opening 15h… Guide part
15i ... Sleeve seal seating surface 15i1 ... Lower part 15j ... Blade mounting seating surface 15j1 ... Step 15k ... Blade mounting seating surface
15m… Positioning protrusion 15n… Mating recess 15p… Rib 15
p1 ... U-shaped groove 15q1, 15q2 ... Guide member 15r ... Rib
15s ... Shaft hole 15t ... Folded curved surface 15u ... Second engaging part 15u1
… Tapers 15v1, 15v2… Legs 16… Bearing members 16a, 16
b ... Bearing 16c ... D cut hole 16d ... Shaft 17 ... Transmission member 17a ... Arm 17b ... Slot 18a ... Ground contact 18a1 ... Base 18a2 ...
Locking hole 18a3 ... Arm part 18a4 ... Hemispherical convex part 18b ... Development bias contact 18c ... Charging bias contact 18c1, 18c2
... End 18d ... Conductive member 19 ... Extraction tool 19a ...
Shaft 19a1 ... Screw 19a2 ... Stopper 19b ... Weight 20 ... Stirring gear 20a
... Boss 20b ... Rotary shaft 21 ... Tensile tool 22 ... Paste tool 23 ... Pressing tool 24 ... Shutter mechanism 24a ... Shutter arm 24a1 ... Shaft part 24a2 ...
Rotation restriction part 24a3 ... Support part 24a4 ... Projection part 24b ... Shutter joint 24b1 ... Rotation center part 24b2 ... Rotation restriction part 24c
... Shutter part 24c1 ... Rotation center part 24c2 ... Locking holes 24d, 24e ... Shaft pressing 24d1, 24e1 ... Support part 24d2 ... Projection part 24d3 ... Groove part 24d4, 24e4 ... Locking claw 24f
Twisted coil spring 25 Tear tape 26 Cover film 27a Drum ground contact pin 27b Development bias contact pin 27
c ... Contact pin for charging bias 28 ... Holder cover 29
… Electrical circuit board 30… Conductive compression spring 31… Drive gear 32…
Disassembly tool 32a ... Rod 33 ... Buffer material 34 ... Opening 35
Contact member 36 Partition plate 37 High-density polyethylene sheet 38 Lubricant 39a Compression spring 39b Lever 40
Eject button 40a ... Pressing protrusion 40b ... Locking claw 40
c ... compression spring 41 ... locking hook 42 ... process cartridge 42a ... cartridge body 42a1 ... rack 42a2 ...
Recess 42b ... Case 42b1 ... Hole 42c ... Eave 42d ... Tension spring 43 ... Image forming device 44 ... Cartridge insertion window
45 ... Spring 46 ... Thin plate 47 ... Gear 48 ... Shaft 49 ... Guide groove 50 ... Contact 51 ... Spring 52 ... Contact pin 53 ... Shaft 54 ...
Lever 54a ... Shaft 55 ... Compression spring 56 ... Motor 57 ... Blade base 58 ... Load sensor 59 ... Amplifier 60 ... Voltmeter

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] March 22, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Fig. 36

[Correction method] Change

[Correction content]

FIG. 36 is a table showing the relationship between blade contact pressure and toner average particle diameter.

Continuation of front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location G03G 21/00 310 6605-2H (72) Inventor Hiroaki Miyake 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Yoshinori Sugiura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (15)

[Claims] 1. A charging roller mounting method for mounting a charging roller to a frame, wherein when mounting the charging roller to the frame, a movement allowable amount in a direction orthogonal to an axis of the charging roller is set to one end side and the other end side of the charging roller. The charging roller mounting method is characterized in that the charging roller is mounted differently on the side. 2. The method of mounting a charging roller according to claim 1, wherein the charging roller is elastically pressed by a spring in a direction orthogonal to the axis. 3. The shaft of the charging roller is supported by a bearing, and the amount of movement in the direction orthogonal to the axis of the shaft in the bearings provided at one end side and the other end side of the charging roller is different. The method according to claim 1, wherein the charging roller is attached. 4. A process cartridge mountable to a main body of an image forming apparatus, comprising: an image carrier, a charging roller for charging the image carrier, and the charging roller in a direction orthogonal to an axis of the charging roller. A process cartridge comprising: a supporting unit configured to support the charging roller so that the one end side and the other end side of the charging roller are different from each other. 5. The moving allowance in a direction orthogonal to the axis of the charging roller is set to be larger on the driving force receiving portion side of the photosensitive drum as the image bearing member than on the other end side. 4. The process cartridge according to item 4. 6. The process cartridge according to claim 4, wherein the process cartridge further comprises a developing means as a process means, which is integrally formed into a cartridge. 7. The process cartridge according to claim 4, wherein the process cartridge further comprises a cleaning unit as a process unit that is integrally formed as a cartridge. 8. The charging roller is elastically pressed by a spring in a direction orthogonal to the axis line, and is rotated by being brought into contact with a photosensitive drum as the image carrier. Process cartridge described. 9. An image forming apparatus capable of mounting a process cartridge and forming an image on a recording medium, comprising: an image carrier, a charging roller for charging the image carrier, and the charging roller. Supporting means for supporting the charging roller in a direction perpendicular to the axis of the charging roller while allowing the one end side and the other end side of the charging roller to differ, and a mounting means capable of mounting a process cartridge, An image forming apparatus including: a drive source that applies a rotational drive force to an image carrier that the image carrier has; and a transport unit that transports a recording medium. 10. The allowance of movement of the charging roller in a direction orthogonal to the axis of the charging roller is set to be larger on the driving force receiving portion side of the photosensitive drum as the image carrier than on the other end side. 9. The image forming apparatus according to item 9. 11. The image forming apparatus according to claim 9, wherein the image forming apparatus is an electrophotographic copying machine. 12. The image forming apparatus according to claim 9, wherein the image forming apparatus is a laser beam printer. 13. The image forming apparatus according to claim 9, wherein the image forming apparatus is a facsimile apparatus. 14. A method of assembling a process cartridge, wherein a charging roller is attached to a frame of a process cartridge, wherein when the charging roller is attached to the frame, a movement allowable amount in a direction orthogonal to an axis of the charging roller is set at one end side of the charging roller. And the other end side differently,
After that, the method of assembling the process cartridge is characterized in that the charging roller is brought into contact with the image carrier. 15. The charging roller is attached to an upper frame, the image carrier is attached to a lower frame, and the charging roller contacts the image carrier by locking the upper frame and the lower frame. 15. The method for assembling a process cartridge according to claim 14, wherein: