JP3224482B2 - Process cartridge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to vibration damping of a developer stirring means of an image forming apparatus such as a laser beam printer and a copying machine.

[0002]

2. Description of the Related Art In an image forming apparatus using electrophotography, if the image forming apparatus is used for a long time, it is necessary to replace a photosensitive drum, replenish or replace a developer, and other adjustments, cleaning and replacement.
However, such maintenance work has been practically difficult except for service personnel having specialized knowledge. As a means for solving this problem, a process cartridge has been commercialized in which an image forming means such as an image carrier (photosensitive drum), a developing device, and a cleaning device are used as a unit body. As a result, the user can easily perform maintenance and replacement by himself / herself, and high quality image quality can be obtained at low cost.

FIG. 6 is a view showing a method of incorporating the process cartridge 100 into an image forming apparatus 200 using electrophotography. As shown in the figure, a positioning shaft 100B and an insertion guide 100A
The image forming apparatus 200 includes a bearing 200B fitted to the positioning shaft 100B, an insertion guide 10
A groove 200A that fits with 0A is provided. Therefore,
The user only needs to align the insertion guide 100A along the groove 200A to move the process cartridge 100 to the image forming apparatus 2.
00 can be easily incorporated.

FIG. 7 is a view showing a state where the process cartridge 100 is incorporated in the image forming apparatus 200.
The installed process cartridge is fixed by its own weight and the pressing force of a transfer roller described later.

As shown in FIG. 4 which is a sectional view, the process cartridge 100 fixed in this manner is roughly divided into an image carrier 6, a developer container 4 containing a developer t, a developing unit 3 for developing, The image carrier 6 is divided into a cleaning unit 2 for storing a used developer t, and these image forming process devices are integrated as a unit body. A well-known electrophotographic process is used as an image forming method.

First, when a laser beam L emitted by an image signal from a laser optical system (not shown) irradiates the image carrier 6, an electrostatic latent image is formed and the developer t is stored in the developer container 4. Is pumped up by a stirring sheet member 5 made of PET or the like, and is fed into the developing unit 3 from the opening 11. A small gap between the surface of the developing roller 7 and the tip of the developing blade 8 coats the surface of the developing roller 7 with a thin and uniform coating of the developer t. It adheres to the surface of the body 6 and is imaged.

Next, the printing sheet material P is conveyed from a feeding device (not shown) at a predetermined timing with respect to the image signal, and the transfer roller 10 transfers the developer t onto the sheet material. P is image-fixed by a fixing device (not shown) and is discharged out of the machine. The developer t remaining on the surface of the image carrier 6 is scraped off by the cleaning blade 9 and stored in the cleaning container 2.

The above-described process cartridge 100
In the image forming apparatus in which the transfer roller 1 is incorporated,
Reference numeral 0 denotes a pressing force F applied by the pressing spring 22 via the bearing 21 and the center shaft 20 to transfer the developer t attached to the surface of the image carrier 6 to the sheet material P. The transfer roller 10 is made of a relatively soft material such as a sponge material so that a nip is formed by the pressing force F. The pressing force F positions the process cartridge 100 and affects the contact angle between the sheet material P and the image carrier 6.

The nip, pressing force, and contact angle of the transfer roller 10 affect transfer conditions and are important factors for determining the density of a printed image, and are set to optimal values for each image forming apparatus. I have.

[0010]

However, in the above-mentioned prior art, since the process cartridge is incorporated in an image forming apparatus such as an LBP, the developer container is made as compact as possible, but is formed so that a large amount of developer can be loaded. Had restrictions.

In other words, the bottom is arc-shaped so that the developer can be scooped up easily. However, the developer container lid 4A is limited in order to make it easy to incorporate the cleaning unit 2 therein and because of the mechanism of the process cartridge. It had to be arranged at a height, and the distance from the stirring shaft 5A could not be sufficiently taken. Further, in order to load a large amount of developer in a limited space, the inner side surface 4E needs to be flat.

Accordingly, the stirring sheet member 5 serving as stirring means which rotates around the stirring shaft 5A at a constant speed to carry the developer t, presses and slides inside the developer container 4, and as shown in FIG. The reaction force from the developer container lid 4A causes the deformation in an arc shape, but since the shaft 5A rotates in the direction of arrow D, the direction of the return force of the stirring sheet member 5 changes, and the developer container lid 4A
The stirring sheet member 5 is repelled in the direction of arrow B and vibrates.

In addition, the process cartridge 100
In order to facilitate attachment and detachment, the cartridge is fixed only by the own weight of the cartridge by the positioning shaft 100B and the insertion guide 100A and the pressing force of the transfer roller 10, and is likely to vibrate.

Therefore, the cartridge picks up and vibrates the vibration of the stirring sheet member 5, and the pressing force, the positional relationship and the nip width between the image carrier 6 and the transfer roller 10 which sandwich the sheet material P are changed, and the printing of the developer t is performed. There was a phenomenon that the transfer conditions for the sheet material P were changed, and that the print image had uneven printing due to the stirring period.

It is an object of the first invention according to the present invention to solve the above-mentioned problems and to provide a process cartridge capable of suppressing vibration of a stirring sheet member and forming an inexpensive and high-quality image.

In addition, in addition to the above objects, the second invention according to the present application includes a stirring sheet member capable of satisfactorily stirring the developer in a limited space. It is an object of the present invention to provide a process cartridge capable of reliably suppressing vibration.

Still another object of the third invention of the present application is to provide a process cartridge capable of reliably suppressing vibration of the stirring sheet member with a simple configuration, in addition to the above objects.

Another object of the present invention is to provide, in addition to the above objects, a process cartridge having a means that is excellent in incorporation and that can reliably prevent vibration of the stirring sheet member.

Still another object of the present invention is to provide, in addition to the above objects, a process cartridge capable of reliably preventing the stirring sheet member from vibrating for a long period of time.

Another object of the present invention is to provide, in addition to the above objects, a process cartridge capable of reliably preventing vibration of a stirring sheet member while preventing accumulation of a developer. I do.

[0021]

According to a first aspect of the present invention, there is provided a developer container including at least a developer container as a unit, and pressing and sliding on an inner wall of the developer container. With stirring means for stirring the internal developer,
In the process cartridge detachably mountable to the image forming apparatus, an anti-vibration means is provided inside the developer container to contact the agitating means on the orbit of the agitating means and to maintain a pressing and sliding state. Achieved.

According to the second aspect of the present invention,
According to the first object of the present invention, in the first aspect, the agitating means is an elastic body rotatably disposed inside the developer container, and the vibration isolating means is configured to abut along a rotating direction of the agitating means. This is achieved by being provided.

Further, according to a third aspect of the present invention, the above object is achieved in the second aspect, wherein the vibration isolating means is an elastic sheet member.

According to a fourth aspect of the present invention,
The object is achieved in the second aspect of the invention in that the developer container has a two-piece structure of a container and a lid, and the vibration isolating means is provided on the lid of the developer container.

Further, according to a fifth aspect of the present invention, the above object is achieved in the fourth aspect, wherein the vibration isolating means is an elastic sheet member, and agitating from the inner surface of the developer container lid to the inner surface of the developer container. This is achieved by providing a rib integrally formed with the developer container lid between the inner surface of the developer container lid and the elastic sheet member.

According to the sixth aspect of the present invention,
The above object is achieved in the third aspect of the present invention by providing the elastic sheet member with a hole through which the developer can pass.

[0027]

According to the first aspect of the present invention, the agitating means agitates the developer while pressing and sliding on the inner wall of the developer container. Vibration does not occur due to release of the pressing force of the stirring means.

According to the second aspect of the present invention,
The stirring means is an elastic body rotatably arranged inside the developer container, so that the developer is reliably stirred while pressing and sliding on the inner wall of the developer container, and the vibration isolating means is moved in the rotation direction of the stirring means. Since they are arranged so as to be in contact with each other, the pressing and sliding state is maintained and vibration is prevented.

Further, according to the third aspect of the present invention, since the vibration isolating means is an elastic sheet member, the vibration isolating means can be easily attached to a conventional device to reliably prevent vibration.

Further, according to the fourth invention of the present application,
Since the developer container has a two-piece structure of a container and a lid, and the anti-vibration means is provided on the lid of the developer container, the incorporation of the anti-vibration means is improved.

Further, according to the fifth aspect of the present invention, the vibration damping means is an elastic sheet member, which is attached in an arc shape from the inner surface of the developer container lid to the inner surface of the developer container in the rotation direction of the stirring sheet member. Since a rib formed integrally with the developer container lid is provided between the inner surface of the developer container lid and the elastic sheet member, the elastic sheet member relatively weak in bending force is supported by the rib. In addition, the pressing and sliding state of the stirring means is maintained to suppress vibration.

According to the sixth aspect of the present invention,
Since the elastic sheet member is provided with a hole through which the developer can pass, the developer does not accumulate on the elastic sheet member, and the loaded developer is effectively used.

[0033]

An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view of a process cartridge 1 according to an embodiment of the present invention.

The image forming method of the process cartridge 1 of this embodiment uses the well-known electrophotographic process described in the conventional example, 2 is a cleaning unit, 3 is a developing unit,
Is a developer container, 5 is a stirring sheet member, 6 is an image carrier, 7
Denotes a developing roller, 8 denotes a developing blade, 9 denotes a cleaning blade, 10 denotes a transfer roller, t denotes a developer, and P denotes a printing sheet material. The apparatus according to the present embodiment forms an image and performs printing as in the conventional example with the above configuration.

Here, the stirring sheet member 5 as the stirring means, the elastic sheet member 12 as the vibration isolating means, and the backup rib 4C according to the present invention will be described with reference to FIGS.

FIG. 2 is a view of the developer container cover 4B as viewed from the direction of arrow A, and 12 is an elastic sheet member made of PET or the like. There are two holes in the center so that the stirred developer t does not accumulate, and the tip is also saw-shaped. The elastic sheet member 12 is adhered to a hatched portion of the developer container lid 4B with a double-sided tape or the like. Reference numeral 4C denotes a rib provided inside the developer container cover 4B, and a surface which abuts the stirring sheet member 5 so as to be able to rotate smoothly is a curved surface.

Therefore, as shown in FIG. 3, even when the stirring sheet member 5 moves from the developer container lid 4B to the side surface 4E, the stirring sheet member 5 applies its return force to the elastic sheet member 1.
2 and the backup rib 4C.

The developer t in the developer container 4 is rotatably conveyed by a stirring sheet member 5 which is driven to rotate at a predetermined speed, and is opened to the developing unit 3 which is continuously arranged via the developer container 4 and the partition 13. It is intermittently fed through 11 and supplied.

In the conventional example of FIG. 5, there is no mechanism for regulating the return force of the stirring sheet member at the corner of the developer container.
In some cases, the sheet member was flipped, the cartridge vibrated, and unevenness occurred in the print image in the stirring period.

However, in this embodiment, the developer container lid 4B
By providing the elastic sheet member 12 that regulates the return force of the stirring sheet member 5 from the inner surface to the developer container inner side surface 4E, the stirring sheet member 5 slides smoothly.

Further, the provision of the backup rib 4C supports the elastic sheet member 12 which is relatively weak in bending force, counters the return force of the stirring sheet member 5, and maintains a bow shape. Printing unevenness in the cycle disappeared.

[0042]

As described above, the first embodiment according to the present application is described.
According to the invention, the vibration isolator is arranged so as to contact the agitator on the orbit of the agitator, thereby preventing vibration of the agitator and preventing unevenness that has conventionally occurred in the agitator cycle. , Image quality can be improved.

According to the second aspect of the present invention,
The stirring means is an elastic body rotatably disposed inside the developer container, and the vibration isolating means is disposed so as to contact along the rotation direction of the stirring means, so that the developer is surely stirred, In addition, vibration can be reliably prevented.

Further, according to the third aspect of the present invention, since the vibration isolating means is an elastic sheet member, the vibration isolating means can be easily attached to a conventional apparatus, and can reliably prevent vibration.

According to the fourth aspect of the present invention,
Since the developer container has a two-piece structure of a container and a lid, and the anti-vibration means is provided in the lid of the developer container, the incorporation of the anti-vibration means is improved, and the anti-vibration performance described in the first invention is improved. It can be realized at low cost and productivity.

Further, according to the fifth invention of the present application, the vibration isolating means is an elastic sheet member, and is attached from the inner surface of the developer container lid to the inner surface of the developer container in an arc shape in the rotating direction of the stirring sheet member. Since the rib is provided integrally with the lid of the developer container between the inner surface of the lid of the developer container and the elastic sheet member, the pressing and sliding state of the stirring means can be maintained for a long time, and the vibration can be suppressed.

According to the sixth invention of the present application,
Because the elastic sheet member has a hole through which the developer can pass,
The developer does not accumulate on the elastic sheet member, and the load amount can be used efficiently.

[Brief description of the drawings]

FIG. 1 is a sectional view of a process cartridge according to an embodiment of the present invention.

FIG. 2 is a bottom view of a developer container lid 4B according to an embodiment of the present invention.

FIG. 3 is a view showing the movement of a stirring sheet member according to one embodiment of the present invention.

FIG. 4 is a sectional view of a conventional process cartridge.

FIG. 5 is a diagram for explaining a conventional problem.

FIG. 6 is a diagram illustrating a method of incorporating a process cartridge into a conventional image forming apparatus main body.

FIG. 7 is a diagram illustrating a state where a conventional process cartridge is incorporated in an image forming apparatus main body.

[Explanation of symbols]

 Reference Signs List 1 process cartridge 4 developer container 5 stirring sheet member (stirring means) 12 elastic sheet member (vibration isolating means) 4C backup rib

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-52-148133 (JP, A) JP-A-63-197978 (JP, A) JP-A-64-48079 (JP, A) 142066 (JP, U) Hikaru 1-169260 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/08 110 G03G 21/18

Claims (6)

(57) [Claims] 1. A process which includes at least a developer container as a unit body, and has a stirring means for stirring the developer inside the developer container while pressing and sliding the inner wall of the developer container, and which is detachable from the image forming apparatus. A process cartridge, wherein a vibration damping means is provided inside the developer container so as to contact the stirring means on the trajectory of the stirring means to maintain a pressing and sliding state. 2. The stirring means is an elastic body rotatably disposed inside the developer container, and the vibration isolating means is disposed so as to abut along the rotation direction of the stirring means. The process cartridge according to claim 1, wherein 3. The process cartridge according to claim 2, wherein the vibration isolating means is an elastic sheet member. 4. The process cartridge according to claim 2, wherein the developer container has a two-piece structure of a container and a lid, and the vibration isolating means is provided on the lid of the developer container. 5. The vibration damping means is an elastic sheet member, which is attached from the inner surface of the developer container lid to the inner surface of the developer container in an arc shape in the rotation direction of the stirring means. The process cartridge according to claim 4, wherein a rib formed integrally with the lid of the developer container is provided between the ribs. 6. The process cartridge according to claim 3, wherein the elastic sheet member has a hole through which the developer can pass.