JPH07295460A - Process cartridge and image forming apparatus - Google Patents

Abstract

PURPOSE:To lessen the impact against an image carrying body at the time of setting a process cartridge and lessen the number of assembly manhour in order to make the cost down by joining frame bodies in the way they can rotate on a supporting axis formed in one of the bodies and pressing a developing member toward the image carrying body with a pressing member to which a handle member is attached. CONSTITUTION:The image forming apparatus has a developing means 10 having a developing member, a cartridge frame body so composed to join a first frame body 12 having an image carrying body with a second frame body 13 holding the developing means 10, and a handle member 18 attached to the first frame body 12. The first frame body 12 and the second frame body 13 are so joined as to rotate on a supporting axis formed in either one of the frames and the developing member is pressed in the direction toward the image carrying body by a pressing member formed in the handle member 18. At the time of insertion of a process cartridge B into the image forming apparatus while the handle member 18 being held, since the handle member 18 is attached to the first frame body 12 which holds the image carrying body, the developing member is not pressed unnecessarily and no impact is caused between the image carrying member and the developing member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process cartridge which is removably mounted in a device employing an electrophotographic system or an electrostatic recording system, and an image forming apparatus which mounts the process cartridge and forms an image on a recording medium. .

[0002]

2. Description of the Related Art In an image forming apparatus such as a printer, a latent image is formed by selectively exposing an image carrier uniformly charged by a charger, and the latent image is developed by a developer by a developer. At the same time as forming an image, the image formed by the developer is transferred to a recording medium to record an image. In such an apparatus, maintenance of each member is performed by a professional service person, which may be inconvenient for the user.

Therefore, as shown in FIG.
50, a charger 51, a developing device 52, a cleaning unit 53, etc. are integrated into a cartridge to form a cartridge, so that the user loads the cartridge into the apparatus main body,
It has been put into practical use that replenishment of the developer and replacement of the parts of the image bearing member that have reached the end of their life are made possible and the maintenance is easy.

In such a process cartridge, a first frame 54 for holding the image carrier 51, the cleaning unit 53, etc., and a second frame 55 for holding the developing roller 52a, the toner storage unit 52b, etc. There is one in which the cartridge frame is constructed by combining the above. In this connection, the first frame body 54 and the second frame body 55 are rotatably connected to each other about a support shaft, and the developing roller 52a is connected to the image carrier 50 side via a ring member 52c by a spring. It is urged to maintain a constant gap (about 300 μm) between the two.

Further, the process cartridge is provided with a rib 56 as a grip portion near the toner storage portion of the second frame so that the process cartridge can be easily held when it is mounted in the image forming apparatus, and the rib 56 is inserted into the image forming apparatus while holding the portion. I am trying.

[0006]

However, when the process cartridge is mounted on the image forming apparatus,
When the rib 56 portion is forcefully inserted into the image forming apparatus, the first frame 54 vibrates, and the developing roller 52a and the image carrier 50 are oscillated.
May collide with.

Further, if the rib 56 is strong, the toner may be blown out from the gap below the developing roller 52a because the toner is sealed in the toner storage portion 52b.

Further, even when the first frame body 54 and the second frame body 55 are joined together, the image carrier 50 after the two frame bodies 54, 55 are joined together.
On the other hand, it is necessary to assemble a spring for urging the developing roller 52a, resulting in a large number of assembling steps.

The present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to reduce the impact on the image carrier at the time of mounting to the image forming apparatus and to prevent the toner from blowing out. The present invention provides a process cartridge capable of reducing the number of assembling steps and cost, and an image forming apparatus to which the process cartridge can be mounted.

[0010]

A typical structure according to the present invention for achieving the above object is an image carrier, a developing means having a developing member acting on the image carrier, and the image carrier. A first frame body for holding a cartridge frame body and a second frame body for holding the developing means;
A handle member attached to the frame body, and the first frame body and the second frame body are rotatably coupled about a support shaft provided in one of the frame bodies, and The process cartridge is characterized in that the pressing member provided on the handle member biases the developing member toward the image carrier.

Further, the image forming apparatus is characterized in that a mounting means for mounting the process cartridge is provided.

[0012]

In the above construction, when the process cartridge is inserted into the image forming apparatus by holding the handle member, the handle member is attached to the first frame body holding the image carrier, so that the developing member is It is possible to prevent an impact from being generated between both members without being pressed more than necessary.

When a handle member is attached to the first frame,
The developing member is urged toward the image carrier by the pressing member provided on the handle member. Therefore, it is not necessary to separately attach a spring or the like for urging the developing member to the image carrier.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a first embodiment will be described as a preferred embodiment of the present invention, a second embodiment will be described next as another example, and finally another embodiment will be described.

[First Embodiment] FIG. 1 is a structural explanatory view of an image forming apparatus in which a process cartridge according to the first embodiment is mounted, and FIG. 2 is a structural explanatory view of a process cartridge,
FIG. 3 is an explanatory view of the structure of the mounting means for the process cartridge, and FIGS. 4 to 6 are explanatory views of the assembly structure of the cartridge frame. Here, as the order of description, first, the overall configuration of the image forming apparatus and the process cartridge will be described.
Next, the coupling structure of the first frame body and the second frame body that form the cartridge frame body will be described.

{Overall Configuration} This image forming apparatus A is shown in FIG.
As shown in FIG. 3, a light image based on image information is emitted from the optical system 1 to form a toner image on the photosensitive drum, which is an image carrier. Then, in synchronization with the formation of the toner image, the recording medium 2 is conveyed from the cassette 3a along the reverse conveyance guide 6a by the conveyance means 3 including the pickup roller 3b, the pair of conveyance rollers 3c and 3d, and the pair of registration rollers 3e. In addition, in the image forming unit formed as the process cartridge B, the toner image formed on the photosensitive drum is transferred to the recording medium 2 by applying a voltage to the transfer roller 4 serving as the transfer unit, and the recording medium 2 is heated by the heater. The transfer toner image is fixed to the recording medium 2 by being conveyed to the fixing means 5 including a fixing rotating body 5b having a built-in 5a and a driving roller 5c for pressing and conveying the recording medium 2 to the rotating body 5b. Then, the recording medium 2 is ejected from the discharge roller pair 3f, 3
It is configured to be conveyed by g and 3h and discharged to the discharge section 7 through the reverse conveyance guide 6b.

On the other hand, in the process cartridge B forming the image forming section, as shown in FIG. 2, the photosensitive drum 8 having a photosensitive layer is rotated, and the surface thereof is applied with a voltage to a charging roller 9 which is a charging means. Is uniformly charged, the light image from the optical system 1 is exposed to the photosensitive drum 8 through the exposure unit to form a latent image, and the latent image is developed by the developing means 10. The developing means 10 includes a toner storage portion 10a.
The toner inside is sent out by the toner sending member 10b, and the fixed magnet
While rotating the developing roller 10d having the built-in 10c, a toner layer to which a triboelectric charge is applied by the developing blade 10e is formed on the surface of the developing roller 10d, and the toner is transferred to the photosensitive drum 8 according to the latent image. As a result, a toner image is formed and visualized. And the transfer roller 4
After the toner image is transferred to the recording medium 2 by applying a voltage having a polarity opposite to that of the toner image to the recording medium 2, the cleaning blade 11a scrapes off the toner remaining on the photoconductor drum 8 and the scooping sheet 11b scoops away the waste toner. The cleaning means 11 collecting in the reservoir 11c is configured to remove the residual toner on the photosensitive drum 8.
Each component such as the photosensitive drum 8 is housed in a cartridge frame body formed by connecting the first frame body 12 and the second frame body 13 into a cartridge, and is a cartridge provided in the apparatus main body. It is detachably attached to the attachment means. In order to smoothly perform the attachment / detachment operability of the process cartridge B at the time of attachment / detachment, as shown in FIG. 3, ridge guide members 14 are provided on both sides of the cartridge frame in the longitudinal direction. On the other hand, the image forming apparatus A is provided with a cartridge mounting means. The mounting means is provided with a cartridge mounting space when an opening / closing cover (not shown) is opened, and guide rails 15 for guiding the guide member 14 are provided on the left and right inner side surfaces of the space area. An arcuate positioning groove 16 is provided at a predetermined position.

Therefore, when the process cartridge B is mounted on the image forming apparatus A, the guide member 14 is inserted along the guide rail 15 and fixed coaxially with the rotation axis of the photosensitive drum 8 of the cartridge B. Locating pin
The positioning of the cartridge B is performed by fitting 17 into the positioning groove 16 of the image forming apparatus A, and the guide member 14 is supported by the guide rail 15 so that the attitude of the cartridge B is regulated and positioned. At this time, a handle member 18 is attached so that the process cartridge B can be easily held.

{Coupling Structure of First Frame and Second Frame} Next, with respect to the connecting structure of the first frame 12, the second frame 13 and the handle member 18 of the process cartridge B, FIGS. It will be described with reference to FIG. 4 is a perspective view showing the assembled state of the first frame body 12, the second frame body 13 and the handle member 18, FIG. 5 is a partial sectional view of the assembled state, and FIG. 6 is a part in the assembled state. It is a perspective view.

As shown in FIG. 4, the handle member 18 has a base 18
A grip portion 18b having a diameter of about 50 mm is formed in the longitudinal direction of the end portion of a, and a positioning portion 18c and a spring mounting portion 18d are provided at both ends on the opposite side.

The positioning portion 18c projects downward from the base body 18a, and restricts the position of the coupling support shaft of the second frame body 13 which will be described later in only one of the two end portions, while preventing the other from coming off. Is going. The spring attachment portion 18d is provided in parallel with the positioning portion 18c, and a compression spring 19 is attached to the tip of the spring attachment portion 18d so as to project further downward than the positioning portion 18c.

Further, on the surface depending on the base 18a,
A fitting square hole 18e for positioning the first frame 12 by the positioning member 20 is provided.

On the other hand, the first frame 12 is held by the photosensitive drum 8 and the cleaning means 11 such as the cleaning blade 11a, and the second frame 13 is held by the developing roller 11d and the developing blade 11e.
Holds the developing member such as.

Arm portions 13a are provided on both sides in the longitudinal direction of the second frame body 13, and coupling support shafts 13b are provided on the arm portions 13a so as to project laterally. Further, a spring receiving recess 13c for receiving the compression spring 19 is formed on the top surface of the arm portion 13a.

Further, the first frame 12 is provided with a coupling recess 12a into which the coupling support shaft 13b is fitted, and a through hole 12b through which the positioning portion 18c of the handle member 18 and the compression spring 19 penetrate at the upper part thereof. , 12c are provided. Further on the side surface is a handle member 18
A fitting square hole 12d is provided for positioning and fastening with the positioning member 20.

Now, the first frame body 12 and the second frame body 13 of the above construction
In order to connect the handle member 18, first, the connecting support shaft 13b of the second frame body 13 is fitted into the innermost part of the connecting recess 12a of the first frame body 12 (step of FIG. 4), and then both frame bodies are joined. The handle member 18 is inserted from above 12 and 13 (step of FIG. 4). That is, the positioning part
18c is inserted into the through hole 12b, and the compression spring 19 is inserted into the through hole.
After passing through 12c and receiving it in a compressed state in the spring receiving recess 13c, the positions of the handle positioning fitting square holes 18e on both sides are aligned. After that, the positioning members 20 are inserted from both sides (step of FIG. 4) to complete the assembly. The outer diameter of the positioning member 20 has a press-fitting tolerance with respect to the fitting square hole 18e of the handle member 18 and the fitting square hole 12d of the first frame body 12, and is provided with a claw 20a for retaining. .

By the above-mentioned assembly, as shown in FIGS. 5 and 6, the coupling support shaft 13b is held by the first frame 12 and the handle member 13. As a result, the first frame body 12 and the second frame body 13
Is rotatably coupled about a coupling support shaft 13b, and ring members (not shown) attached to both ends of the developing roller 10d in the longitudinal direction are in pressure contact with the photosensitive drum 8 and the developing roller for the photosensitive drum 8 is connected. A 10d gap is positioned. Further, the elasticity of the compression spring 19 presses the developing roller 10d toward the photosensitive drum 8, so that the gap is stably maintained. When the first frame 12 and the second frame 13 are combined as described above, the drum gear 21 attached to the end of the photosensitive drum 8 and the roller gear 22 attached to the end of the developing sleeve 10d mesh with each other. Then, the driving force can be transmitted.

With the above-described structure, the first frame body 12 and the second frame body 13 can be joined by the handle member 18 which is one component having the handle function, and the second frame body 13 is pressed at the same time. You can do it. Conventionally, the coupling and the pressurization were separately performed at both ends in the longitudinal direction of the frame body, but by configuring as in this example, the assembly process can be shortened,
It is possible to reduce the cost by reducing the number of parts.

Also, when disassembling the cartridge frame for recycling, the first frame 12, the second frame 13 and the handle member 18 can be easily disassembled simply by pulling out the positioning members 20 from both sides.

As a modified example of the present embodiment, instead of press-fitting the positioning member 20 into the fitting square holes 12d and 18e, a dowel is projected on the first frame 12 and the dowel is fitted into the fitting square hole. The positioning member 20 may be welded after the 18e is fitted. By doing this, a more reliable connection is achieved and rigidity is increased. Further, the compression spring 19 can obtain the same effect by using a leaf spring.

[Second Embodiment] Next, a second embodiment of the coupling construction of the first frame member, the second frame member and the handle member will be described with reference to FIG. The members having the same functions as those in the first embodiment described above are designated by the same reference numerals.

In the above-described first embodiment, the positioning member 20 is used when the handle member 18 is attached to the first frame body 12. However, in the holding, the handle member 18 is attached to the first frame body 12 by screws. is there.

That is, as shown in FIG. 7, the base member 18a of the handle member 18 is provided with a through hole 24 for the screw 23 in the vertical direction, and the first frame 12 is provided with a screw hole 25 for allowing the screw 23 to pass therethrough. It is provided. Therefore, the first frame 12 and the fitting holes 12d and 18e provided on the side surfaces of the handle member 18 provided in the first embodiment are not necessary. Further, the positioning of the handle member 18 with respect to the first frame body 12 is performed by a positioning portion for positioning the first frame body 12 and the second frame body 13.
Perform at 18c.

The first frame body 12, the second frame body 13 and the handle member
The assembly of 18 is performed by first inserting the second frame into the coupling recess 12a of the first frame 12.
The coupling support shaft 13b of the frame body 13 is inserted (step of FIG. 7), and the positioning portion 18c of the handle member 18 and the compression spring 19 are inserted through the through holes from above.
12b and 12c are penetrated (process of FIG. 7), and finally screw 23
Are concluded (step of FIG. 7).

With this structure, in addition to the same effects as those of the first embodiment described above, the first frame 12 and the fitting square holes 12d and 18e of the side surface of the handle member 18 are provided in the first embodiment. Although it was necessary to perform the alignment, in the second embodiment, since the handle member 18 directly positions the first frame 12, the alignment work is unnecessary. Also, replace the positioning member 20 with a screw.
Since it is fixed by 23, the cost can be reduced.

[Other Embodiments] Next, other embodiments of each member constituting the above-mentioned process cartridge and image forming apparatus will be described.

The process cartridge B according to the present invention is not limited to the case of forming a single color image as described above, but a plurality of developing means are provided to form a plurality of color images (for example, a two color image, a three color image or a full color image). It can be suitably applied to a cartridge to be formed.

As the developing method, various known developing methods such as a two-component magnetic brush developing method, a cascade developing method, a touchdown developing method and a cloud developing method can be used.

Further, the image carrier is not limited to the above-mentioned photosensitive drum, but includes the following, for example. First, a photoconductor is used as the photoconductor, and as the photoconductor, for example, amorphous silicon, amorphous selenium,
Zinc oxide, titanium oxide, organic photoconductor (OPC) and the like are included. The shape on which the photoconductor is mounted includes, for example, a drum-shaped, belt-shaped rotating body, a sheet-shaped body, and the like. Generally, a drum-shaped or belt-shaped one is used. For example, in the case of a drum type photoconductor, a photoconductor is vapor-deposited or coated on a cylinder of aluminum alloy or the like. Is.

As for the structure of the charging means, the so-called contact charging method was 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 photosensitive drum to uniformly charge the surface of the drum.

The charging means may be of a blade type (charging blade), a pad type, a block type, a rod type, a wire type or the like, other than the roller type.

Further, as a method for cleaning the toner remaining on the photosensitive drum, the cleaning means may be constituted by using a blade, a fur brush, a magnetic brush or the like.

The above-mentioned process cartridge is
At least an electrophotographic photosensitive member as an image carrier and a developing means are provided. Therefore, as the mode of the process cartridge, in addition to the embodiment described above, for example, the image carrier and the developing means are integrally made into a cartridge which can be attached to and detached from the apparatus main body. There is a unit in which the image carrier and the developing unit and the charging unit or the cleaning unit are integrally made into a cartridge so that the cartridge can be attached to and detached from the apparatus main body.

Further, although the laser beam printer is exemplified as the image forming apparatus in the above-mentioned embodiments, the present invention is not limited to this, and other image forming apparatus such as an electrophotographic copying machine, a facsimile machine, a word processor, etc. It is also possible to use for.

[0045]

As described above, according to the present invention, when the process cartridge is inserted into the image forming apparatus while holding the handle member, the handle member is attached to the first frame for holding the image carrier, The developing member is prevented from being pressed more than necessary, and it is possible to prevent an impact from occurring between both members. Further, since there is no second frame body having a toner storage portion or the like, it is possible to prevent the toner from blowing out from the second frame body.

When the handle member is attached to the first frame,
The developing member is urged toward the image carrier by the pressing member provided on the handle member. Therefore, it is not necessary to separately attach a spring or the like for urging the developing member to the image carrier,
Costs can be reduced by reducing the number of parts and the number of assembly steps.

Therefore, by constructing the process cartridge by accommodating the image carrier and the developing means in the cartridge frame to which the handle member is attached, it is possible to provide the process cartridge which is easy to handle.

Further, by constructing an electrophotographic copying machine, a laser beam printer or the like using the process cartridge, the cartridge can be smoothly attached and detached, and the image carrier or the like can be prevented from being damaged or damaged during the attachment or detachment. It is something that can be done.

[Brief description of drawings]

FIG. 1 is a configuration explanatory diagram of an image forming apparatus in which a process cartridge according to a first exemplary embodiment of the present invention is mounted.

FIG. 2 is a diagram illustrating the configuration of the process cartridge.

FIG. 3 is an explanatory diagram of a configuration for mounting a process cartridge.

FIG. 4 is a perspective explanatory view of an assembled state of a first frame body, a second frame body, and a handle member.

FIG. 5 is a partial cross-sectional view of a state in which a frame body is assembled.

FIG. 6 is a partial perspective view of the frame body in an assembled state.

FIG. 7 is a perspective explanatory view of an assembled state of a first frame body, a second frame body and a handle member according to a second embodiment.

FIG. 8 is a diagram illustrating the mounting of the process cartridge according to the related art.

[Explanation of symbols]

A ... Image forming apparatus, B ... Process cartridge, 1 ... Optical system, 2 ... Recording medium, 3 ... Conveying means, 3a ... Cassette,
3b ... Pickup roller, 3c, 3d ... Conveying roller pair, 3e ... Registration roller pair, 3f, 3g, 3h ... Ejection roller pair, 4 ... Transfer roller, 5 ... Fixing means, 5a ... Heater, 5b ... Fixing rotator, 5c ... Drive rollers, 6a, 6b
... Reversing conveyance guide, 7 ... Ejecting section, 8 ... Photosensitive drum, 9
... charging roller, 10 ... developing means, 10a ... toner storage section, 10
b ... toner feeding member, 10c ... magnet, 10d ... developing roller,
10e ... Developing blade, 11 ... Cleaning means, 11a ... Cleaning blade, 11b ... Squeeze sheet, 11c ... Waste toner reservoir, 12 ... Cartridge frame body, 12 ... First frame body, 12a
... coupling recess, 12b, 12c ... through hole, 12d ... fitting square hole, 13
... second frame, 13a ... arm, 13b ... coupling support shaft, 13c ...
Spring receiving recess, 14 ... Guide member, 15 ... Guide rail, 16
... Positioning groove, 17 ... Positioning pin, 18 ... Handle member, 18a
... Base, 18b ... Handle, 18c ... Positioning, 18d ... Spring mounting, 18e ... Fitting square hole, 19 ... Compression spring, 20 ... Positioning member, 20a ... Claw, 21 ... Drum gear, 22 ... Roller gear, 23
… Screws, 24… Through holes, 25… Screw holes

Claims (10)

[Claims] 1. A process cartridge attachable to and detachable from a main body of an image forming apparatus, an image carrier, a developing unit having a developing member acting on the image carrier, and a first frame member holding the image carrier. A cartridge frame formed by combining a second frame holding the developing unit, and a handle member attached to the first frame; the first frame and the second frame; Is rotatably connected about a support shaft provided on one of the frame bodies, and the developing member is biased toward the image carrier by a pressing member provided on the handle member. Process cartridge characterized in that. 2. The process cartridge according to claim 1, wherein the support shaft is provided on a second frame body, and the support shaft is held by the first frame body and the handle member. 3. The process cartridge according to claim 1, wherein the handle member is configured to be attached to the first frame by a positioning member. 4. The handle member is fixed to the first member by a screw.
The process cartridge according to claim 1 or 2, wherein the process cartridge is configured to be attached to a frame. 5. The process cartridge is configured such that, in addition to the electrophotographic photosensitive member as the image bearing member and the developing unit, a charging unit or a cleaning unit is integrally formed as a cartridge and is attachable to and detachable from the image forming apparatus main body. The process cartridge according to claim 1 or 2, wherein the process cartridge is a cartridge. 6. The process cartridge is capable of being attached to and detached from an image forming apparatus main body by integrally forming a charging means and a cleaning means into a cartridge in addition to the electrophotographic photosensitive member as the image carrier and the developing means. The process cartridge according to claim 1 or 2, wherein the process cartridge is a cartridge. 7. An image forming apparatus for forming an image on a recording medium, wherein a process cartridge is attachable / detachable, an image carrier, a developing unit having a developing member acting on the image carrier, and the image carrier. A first frame body for holding a body, a second frame body for holding the developing means, and a cartridge frame body; and a handle member attached to the first frame body. The first frame member and the second frame member are rotatably coupled to each other about a support shaft provided on one of the frame members, and the developing member is attached to the image carrier by a pressing member provided on the handle member. Mounting means for mounting a process cartridge configured to urge in a direction, transfer means for transferring the image formed on the image carrier to a recording medium, and transport for transporting the recording medium Means, and That the image forming apparatus. 8. The image forming apparatus according to claim 7, wherein the image forming apparatus is an electrophotographic copying machine. 9. The image forming apparatus according to claim 7, wherein the image forming apparatus is a laser beam printer. 10. The image forming apparatus according to claim 7, wherein the image forming apparatus is a facsimile apparatus.