JP2005049514A - Process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process cartridge without causing damage such as flaw and breakage on a member such as a transfer belt when loading the process cartridge even when saving the occupancy space of the process cartridge and a transfer unit or the like. <P>SOLUTION: The process cartridge 2 is provided with an image carrier 1, at least one electrophotographic process means located around the image carrier 1, a cartridge frame body which supports the image carrier 1 and the process means and has a transfer opening which allows the image carrier 1 to open for a transfer means of an image forming device main body and a protection cover 7 which covers the transfer opening. Therein, the process cartridge 2 is attachable and detachable for the image forming device main body. The mounting direction to the image forming device main body is the same with the axial direction of the image carrier and the tip part in the mounting direction of the outer periphery surface of the process cartridge is tapered. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a process cartridge that is detachable from an electrophotographic image forming apparatus such as a copying machine, a facsimile machine, or a printer. More specifically, the present invention relates to a process cartridge comprising an image carrier and at least one means of electrophotographic process means arranged around the image carrier.
[0002]
[Prior art]
Conventionally, many process cartridges have been proposed in which an image carrier and an electrophotographic process unit disposed around the image carrier are made detachable from an image forming apparatus main body (for example, Patent Documents 1 and 2). ).
[0003]
On the other hand, in recent image forming apparatuses, with the spread of personal computers, miniaturized printers, copiers, and the like are desired. However, if the printer or the like is downsized, the space around the process cartridge and the transfer unit must be saved. As a result, it is difficult to secure a sufficient space for separating the units when the units are detached from the image forming apparatus. For this reason, when the process cartridge is tilted when the process cartridge is mounted on the image forming apparatus main body, the edge portion of the photosensitive member protective cover and the cartridge frame constituting the outer peripheral surface of the process cartridge is in the image forming apparatus such as a transfer belt. There is a risk that they will hit the members and damage such as scratches or tears may occur in these members.
[0004]
[Patent Document 1]
JP-A-7-306611 [Patent Document 1]
Japanese Patent Application Laid-Open No. 2002-91266
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, and a first object thereof is to provide a process cartridge as described below. That is, even when the space around the process cartridge, the transfer unit, etc. is saved, the process cartridge does not cause damage such as scratches or tears to members such as the transfer belt when the process cartridge is mounted. The second object is to provide the following process cartridge. That is, even when the space around the process cartridge, the transfer unit, etc. is saved, when removing the process cartridge, or when mounting the transfer unit to the apparatus main body with the process cartridge mounted in the apparatus main body, This is a process cartridge that does not cause damage such as scratches or tears on a member such as a transfer belt.
[0006]
[Means for Solving the Problems]
In order to achieve the first object, the invention of claim 1 includes an image carrier, at least one of electrophotographic process means arranged around the image carrier, the image carrier, and the image carrier. A cartridge frame having a transfer opening that supports the process means and opens the image carrier to the transfer means of the image forming apparatus main body, and a protective cover that covers the transfer opening, and is detachable from the image forming apparatus main body In such a process cartridge, the mounting direction to the image forming apparatus main body is the same as the axial direction of the image carrier, and the tip of the outer peripheral surface of the process cartridge in the mounting direction is tapered. .
According to a second aspect of the present invention, in the process cartridge according to the first aspect, a tip end portion in the mounting direction of the protective cover constituting the outer peripheral surface of the process cartridge is tapered.
According to a third aspect of the present invention, in the process cartridge according to the first or second aspect, a tip end portion in the mounting direction of the cartridge frame constituting the outer peripheral surface of the process cartridge has a tapered shape. is there.
According to a fourth aspect of the present invention, in the process cartridge according to the first, second, or third aspect, the protective cover covers the entire side surface having the transfer opening surface.
In order to achieve the second object, the invention according to claim 5 is the process cartridge according to claim 1, 2, 3, or 4, wherein the front end in the mounting direction of the protective cover constituting the outer peripheral surface of the process cartridge is provided. The end on the opposite side has a tapered shape.
[0007]
According to the first to fifth aspects of the present invention, the tip of the process cartridge outer peripheral surface in the mounting direction is tapered. The taper is configured such that the outer diameter of the process cartridge becomes smaller toward the tip in the mounting direction. Therefore, when the process cartridge is mounted on the image forming apparatus main body, it is less likely to abut against other members provided in the image forming apparatus main body such as a transfer belt as compared with the conventional case. Moreover, even if it hits by any chance, since it is a taper shape, it can prevent that another member is damaged.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, as an image forming apparatus to which the present invention is applied, an embodiment of an electrophotographic printer (hereinafter simply referred to as a printer) will be described.
First, the basic configuration of the printer will be described. FIG. 1 is a schematic configuration diagram showing the printer. In FIG. 1, the printer 100 includes four process cartridges 2Y, 2M, 2C, and 2Bk for forming yellow, magenta, cyan, and black (hereinafter referred to as Y, M, C, and Bk) toner images. ing. These use Y, M, C, and Bk toners of different colors as the image forming agent, but the other configurations are the same and are replaced when the lifetime is reached. A process cartridge 2Y for forming a Y toner image will be described below as an example. As shown in FIG. 2, a drum-shaped photoconductor 1Y, a drum cleaning device 3Y, a charge eliminating device (not shown), a charging device 4Y, a developing device 5Y, and the like are provided. The process cartridge 2Y can be attached to and detached from the printer 100 main body so that consumable parts can be replaced at a time.
[0009]
The charging device 4Y uniformly charges the surface of the photoreceptor 1Y that is rotated clockwise in the drawing by a driving unit (not shown). The surface of the uniformly charged photoreceptor 1Y is exposed and scanned by a laser beam L emitted from an exposure device 53 provided below the process cartridges 2Y, 2M, 2C, and 2Bk in the drawing, and is electrostatic latent for Y. Carry an image. The Y electrostatic latent image is developed into a Y toner image by the developing device 5Y using Y toner. Then, intermediate transfer is performed on the intermediate transfer belt 51. The drum cleaning device 3Y removes the toner remaining on the surface of the photoreceptor 1Y after the intermediate transfer process. The static eliminator neutralizes residual charges on the photoreceptor 1Y after cleaning. By this charge removal, the surface of the photoreceptor 1Y is initialized and prepared for the next image formation. Similarly, in the other process cartridges 2M, 2C, and 2Bk, M, C, and Bk toner images are formed on the photoreceptors 1M, 1C, and 1Bk, and are intermediately transferred onto the intermediate transfer belt 51. The exposure device 53 irradiates the photoconductor with a laser beam (L) emitted from a light source through a plurality of optical lenses and mirrors while scanning with a polygon mirror rotated by a motor.
[0010]
In the lower side of the exposure device 53 in FIG. 1, paper supply means including a paper storage cassette 58, a paper supply roller 57 incorporated therein, a registration roller pair 56, and the like is disposed. The paper storage cassette 58 stores a plurality of transfer papers P, which are recording materials, and a paper feed roller 57 is brought into contact with each uppermost transfer paper P. When the paper feeding roller 57 is rotated counterclockwise in the drawing by a driving means (not shown), the uppermost transfer paper P is fed toward the rollers of the registration roller pair 56. The registration roller pair 56 rotationally drives both rollers to sandwich the transfer paper P, but temporarily stops rotating immediately after sandwiching. Then, the transfer paper P is sent out toward a later-described secondary transfer nip at an appropriate timing. In the sheet feeding means having such a configuration, a recording medium transporting apparatus is configured by a combination of the sheet feeding roller 57 and the registration roller pair 56 corresponding to the timing roller. This recording material transport device transports the transfer paper P from a paper storage cassette 58 serving as storage means to a secondary transfer nip described later.
[0011]
Above the process cartridges 2Y, 2M, 2C, and 2Bk in the drawing, a transfer unit 50 that moves the intermediate transfer belt 51 that is an intermediate transfer member endlessly while being stretched is disposed. The transfer unit 50 includes a cleaning device 60 and the like in addition to the intermediate transfer belt 51. Also provided are four primary transfer bias rollers 61Y, 61M, 61C, 61Bk, a secondary transfer backup roller 62, a tension roller 63, and the like. The intermediate transfer belt 51 is endlessly moved in the counterclockwise direction in the figure by the rotational drive of at least one of the rollers while being stretched around these rollers. The primary transfer bias rollers 61Y, 61M, 61C, and 61BB respectively sandwich the intermediate transfer belt 51 that is moved endlessly between the photoreceptors 1Y, 1M, 1C, and 1BB to form primary transfer nips. Yes. In these methods, a transfer bias having a polarity opposite to that of toner (for example, plus) is applied to the back surface (loop inner peripheral surface) of the intermediate transfer belt 51. All the rollers except for the primary transfer bias rollers 61Y, M, C, and Bk are electrically grounded. The intermediate transfer belt 51 sequentially passes through the primary transfer nips for Y, M, C, and Bk along with the endless movement thereof, and Y, M, and C on the photoreceptors 1Y, M, C, and Bk. , Bk toner images are superimposed and primarily transferred. As a result, a four-color superimposed toner image (hereinafter referred to as a four-color toner image) is formed on the intermediate transfer belt 51.
[0012]
The secondary transfer backup roller 62 sandwiches the intermediate transfer belt 51 between the secondary transfer roller 55 and forms a secondary transfer nip. The visible four-color toner image formed on the intermediate transfer belt 51 is transferred to the transfer paper P at the secondary transfer nip. Then, combined with the white color of the transfer paper P, a full color toner image is obtained. Untransferred toner that has not been transferred onto the transfer paper P adheres to the intermediate transfer belt 51 after passing through the secondary transfer nip. This is cleaned by the cleaning device 60.
[0013]
In the secondary transfer nip, the transfer paper P is sandwiched between the intermediate transfer belt 51 and the secondary transfer roller 55 whose surfaces move in the forward direction, and conveyed in the opposite direction to the registration roller pair 56 side. . When the transfer paper P sent out from the secondary transfer nip passes between the rollers of the fixing device 54, the full-color toner image on the surface is fixed under the influence of heat and pressure. Thereafter, the transfer paper P is discharged out of the apparatus through a pair of paper discharge rollers 67. A stack portion (not shown) is formed on the upper surface of the printer main body, and the transfer sheets P discharged to the outside by the discharge roller pair 67 are sequentially stacked on the stack portion. The residual toner in the form of an intermediate transfer belt is cleaned by the cleaning device 60 and prepared for the next image forming process.
[0014]
Between the transfer unit 50 and the stack portion above the transfer unit 50, a bottle support portion 52 as a container mounting portion is disposed. The bottle support 52 is mounted with toner bottles 65Y, 65M, 65C, and BK that are agent containers for storing Y, M, C, and Bk toners. The 65Y, M, C, and Bk toners in the toner bottle are appropriately supplied to the developing devices of the process cartridges 2Y, M, C, and Bk by toner supply devices (not shown). These toner bottles 65Y, 65M, 65C, and Bk can be attached to and detached from the main body of the printer 100 independently of the process cartridges 2Y, M, C, and Bk.
[0015]
FIG. 3 is a front view showing a schematic configuration of a process cartridge for Y. In the present embodiment, the cartridge frame 8 that forms the casing of the process cartridge includes the photosensitive member 1Y, a drum cleaning device, a charge eliminating device, a charging device, and a developing device. The cartridge frame 8 is provided with a transfer opening so that the photoreceptor 1 </ b> Y contacts the transfer belt 51. This transfer opening is covered with a protective cover 7Y to protect the photoreceptor 1Y as shown in FIG. 3 before the process cartridge 2Y is mounted on the apparatus main body. This is to protect the photoconductor from external stimuli such as external light or foreign matter such as pride when the process cartridge is outside the apparatus main body.
[0016]
The protective cover 7Y is configured such that it can be retracted from or removed from the transfer opening after the process cartridge is mounted on the image forming apparatus. With this configuration, the photoreceptor 1 </ b> Y is exposed to face the transfer belt 51 after being mounted on the apparatus main body. In addition, as a movable means, a shutter system etc. are employable, for example.
[0017]
FIG. 4 is a right side view showing a schematic configuration of the process cartridge 2Y according to the present embodiment. The arrows shown in the drawing indicate the mounting direction of the process cartridge to the image forming apparatus main body. In the present embodiment, the mounting direction of the image forming apparatus main body coincides with the axial direction of the photoreceptor 1Y. With this configuration, the space between the transfer unit such as the intermediate transfer belt and the photosensitive member can be reduced. Therefore, there is no need for a mechanism for retracting the transfer unit greatly, which greatly contributes to downsizing and simplification of the apparatus. In the case where the process cartridge is configured to be attached / detached from the direction other than the photoconductor axial direction, a mechanism for largely retracting the intermediate transfer belt is required, for example. For this reason, the enlargement of an apparatus cannot be avoided and is not preferable.
[0018]
The protective cover 7 according to the present embodiment has a tapered shape 7a as shown in FIG. In the present embodiment, a taper of 5 [mm] in the longitudinal direction and 1 [mm] in the height direction is provided so that the upper surface side of the protective cover 7 moves away from the apparatus main body as it goes to the distal end side in the mounting direction.
The following effects can be obtained by providing a taper at the front end in the mounting direction of the protective cover, which is the most protruding part of the process cartridge and is easily contacted with the transfer unit. That is, the process cartridge is less likely to abut against other members such as a transfer belt when mounted on the apparatus main body. Even in the event of a collision, the taper shape prevents damage such as scratches and tears to the transfer belt and the like.
[0019]
<Modification 1>
Next, a modified example 1 different from the process cartridge mounted on the printer of the above embodiment will be described.
FIG. 5 is a right side view illustrating a schematic configuration of the process cartridge 10 including the protective cover 17 according to the first modification. The basic configuration is the same as that of the above embodiment, but the following points are different. The protective cover 17 according to the first modification has an end on the front side in the mounting direction of the protective cover 17 in addition to the tip end portion with respect to the mounting direction to the apparatus main body having a tapered shape 17a as in the above embodiment. The part also has a tapered shape 17b. Then, after the process cartridge is mounted on the apparatus main body, the protective cover is retracted from the transfer opening so that the photosensitive member 1 is exposed to face the transfer belt 51. Further, when removing the process cartridge from the apparatus main body, and when mounting the transfer unit to the image forming apparatus with the process cartridge mounted on the apparatus main body, the protective cover 17 retracted from the transfer opening prior to the process cartridge is mounted. Is configured to cover the transfer opening again.
In the first modification, as described above, the end of the protective cover 17 on the front side in the mounting direction is also tapered. Accordingly, when the process cartridge is taken out from the apparatus main body, the process cartridge is less likely to hit another member such as a transfer belt as compared with the conventional case. Even in the event of a collision, the taper shape prevents damage such as scratches or tears on the transfer belt or the like. In addition, when the transfer unit is attached to and detached from the apparatus main body with the process cartridge mounted in the apparatus main body, the process cartridge is less likely to hit other members such as a transfer belt as compared with the conventional case. Even in the event of a collision, the taper shape prevents damage such as scratches or tears on the transfer belt or the like.
[0020]
<Modification 2>
Next, a second modified example different from the process cartridge mounted on the printer of the above embodiment will be described.
FIG. 6 is a right side view illustrating a schematic configuration of the process cartridge 20 according to the second modification. The basic configuration is the same as that of the above embodiment, but the following points are different. In the second modification, unlike the above embodiment, the protective cover is configured to be removed before being attached to the apparatus main body. A taper 28a is provided at the front end of the cartridge frame 28 in the mounting direction of the apparatus main body, which is the side in contact with the transfer unit.
In the second modification, the protective cover, which is the most protruding part, is removed before mounting, and a taper 28a is provided at the tip of the cartridge frame 28, which is a part that easily collides with the transfer belt or the like. As a result, when the process cartridge is mounted on the apparatus main body, the process cartridge is less likely to hit another member such as a transfer belt as compared with the conventional case. Even in the event of a collision, the taper shape prevents damage such as scratches or tears on the transfer belt or the like.
[0021]
<Modification 3>
Next, a third modified example different from the process cartridge mounted on the printer of the above embodiment will be described.
FIG. 7 is a front view showing a schematic configuration of the process cartridge 30 according to the third modification. The basic configuration is the same as in the above embodiment, but the area covered by the protective cover is different. In the above embodiment, the protective cover is provided at the transfer opening of the cartridge frame. On the other hand, in the third modification, the entire surface on the side in contact with the transfer unit, which is the side surface with the transfer opening, is covered with the protective cover 39. Thereby, there is no possibility that the transfer unit such as the transfer belt 51 contacts other than the cover of the process cartridge 30. Therefore, damage to peripheral members such as a transfer belt can be prevented more reliably. Further, the protective cover 39 according to the first modification has a tapered shape 39a with respect to the mounting direction to the apparatus main body as in the above embodiment. This makes it difficult for the process cartridge to hit the transfer belt. Even in the event of a collision, the taper shape prevents damage such as scratches and tears to the transfer belt and the like.
[0022]
Note that the printers used in the above-described embodiments and modifications are examples of apparatuses to which the present invention can be applied, and are not limited to these apparatuses. In the above-described embodiments and the like, an example in which a process cartridge includes a photoconductor as an image carrier, a drum cleaning device, a static eliminator, a charging device, and a developing device is described. However, the present invention is not limited to this. . That is, any process cartridge including an image carrier and at least one of electrophotographic process means disposed around the image carrier can be applied.
[0023]
【The invention's effect】
According to the first to fifth aspects of the present invention, even when the space around the process cartridge, the transfer unit, etc. is saved, when the process cartridge is mounted, the transfer belt or the like is damaged or broken. There is an excellent effect of not.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram illustrating a printer according to an embodiment.
FIG. 2 is an enlarged configuration diagram showing a process cartridge for Y of the printer and its surroundings.
FIG. 3 is a front view illustrating a schematic configuration of a process cartridge for Y of the printer.
FIG. 4 is a right side view illustrating a schematic configuration of the process cartridge according to the embodiment.
FIG. 5 is a right side view illustrating a schematic configuration of a process cartridge according to a first modification.
FIG. 6 is a right side view illustrating a schematic configuration of a process cartridge according to a second modification.
FIG. 7 is a front view showing a schematic configuration of a process cartridge according to a third modification.
[Explanation of symbols]
1Y, M, C, Bk photoconductor 2Y, M, C, Bk Process cartridge 3Y, M, C, Bk Cleaning device 4Y, M, C, Bk Charging device 5Y, M, C, Bk Developing device 7 Protective cover 7a Taper Shape 7b Tapered shape 10 Process cartridge 17 Protective cover 17a Tapered shape 20 Process cartridge 28 Cartridge frame 28a Tapered shape 30 Process cartridge 39 Protective cover 39a Tapered shape 50 Transfer unit 100 Printer

Claims (5)

An image carrier, at least one means of electrophotographic process means arranged around the image carrier, the image carrier and the process means are supported, and the image carrier is transferred to the image forming apparatus main body. In a process cartridge that includes a cartridge frame having a transfer opening that is open with respect to the image forming apparatus main body, and a protective cover that covers the transfer opening.
The process cartridge according to claim 1, wherein the mounting direction of the image forming apparatus main body is the same as the axial direction of the image carrier, and a tip end portion of the outer peripheral surface of the process cartridge in the mounting direction is tapered. The process cartridge according to claim 1.
2. A process cartridge according to claim 1, wherein a tip of the protective cover constituting the outer peripheral surface of the process cartridge in a mounting direction is tapered. The process cartridge according to claim 1 or 2,
2. A process cartridge according to claim 1, wherein a tip portion of the cartridge frame constituting the outer peripheral surface of the process cartridge in a mounting direction has a tapered shape. The process cartridge of claim 1, 2, or 3,
The process cartridge, wherein the protective cover covers the entire side surface having the transfer opening surface. The process cartridge of claim 1, 2, 3, or 4
A process cartridge characterized in that the end opposite to the tip in the mounting direction of the protective cover constituting the outer peripheral surface of the process cartridge has a tapered shape.

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