JPH0792885A - Process cartridge and image forming device - Google Patents

Abstract

PURPOSE:To simplify a recycling stage and to improve recycling efficiency by attaching a shaft for rotatably supporting a rotating member to a frame body by thermally caulking at least one boss among plural bosses provided in the frame body. CONSTITUTION:Plural bosses 18a to 18h are provided in the cleaning frame body 12b to which the shaft is attached. In the case of attaching the shaft, two bosses 18a and 18e are inserted through insertion holes 17b1, and thermally caulked. In the case of recycling a process cartridge, a photoreceptor is easily detached from the frame body 12b by cutting off the thermally caulked bosses 18a and 18b. When the shaft is attached to the frame body 12b again, the unused bosses other than the bosses 18a and 18e cut off, for example, the bosses 18b and 18f are used. They are thermally caulked and attached to the shaft. Thus, the frame body need not be exchanged to a new one in the case of recycling.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process cartridge and an image forming apparatus for forming an image on a recording medium.

[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 image carrier to light.
The latent image is visualized with toner, and the toner image is transferred to a recording medium to perform image recording. 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 image carrier, the charging device, the developing device,
By integrating the cleaning unit and the like into an integrated structure into a cartridge, the user can replenish toner and replace parts of the image carrier that have reached the end of life by loading the cartridge into the main body of the apparatus, facilitating maintenance. Things have been put to practical use.

With the recent increase in global environmental protection, such cartridges have begun to be recycled and reused for the purpose of saving resources, saving energy and reducing dust.

For example, in a process cartridge, a charging roller, a developing sleeve, a transfer roller, a fixing roller,
Parts such as cleaning rollers and rollers such as conveying rollers have a long product life and can be used even after the toner in the cartridge is used. Therefore, recently, the cartridge after the toner is used is collected, and the parts such as the rollers are taken out to be recycled and reused (recycled).

[0006]

However, in the process cartridge, in order to rotatably support the image carrier, as shown in FIG. 8, flanges 51a and 51a are provided at both longitudinal ends of the image carrier 50. The flange gear 51b is attached by adhesion or caulking, and the flanges 51a, 51b are attached.
Were rotatably supported by shafts 52, respectively. The shaft 52 was fixed to the cartridge frame 53 with tapping screws 54.

Therefore, if the screws are screwed once and then screwed again when, for example, the process cartridge is recycled, the fastening force becomes weak. Therefore, there is a problem that it is necessary to replace the frame body 53 at the time of recycling, which requires labor and cost.

In order to avoid exchanging the frame 53, there is a method of using a bit insert or a helicoid insert in the screw hole portion so that the screw can be repeatedly fastened. In this case, the bit insert or the helicoid insert is used. There is a problem that the number of parts of the device increases, and it takes time and cost to insert these parts into the frame body 53.

The present invention is to solve the above-mentioned problems of the prior art. The object of the present invention is to eliminate the need to replace the frame during recycling, reduce the number of parts in recycling, and simplify the assembly process. At the same time, it is intended to provide a process cartridge and an image forming apparatus capable of reducing costs.

[0010]

A typical configuration according to the present invention for achieving the above object is an image carrier, at least one process means acting on the image carrier, the image carrier, and A frame supporting the process means,
A shaft for rotatably supporting the rotating member on the frame,
It is characterized in that at least one of the plurality of bosses provided on the frame is attached by thermal crimping to form a process cartridge.

[0011]

In the above structure, when the shaft of the rotating body is attached to the frame body, it is attached by heat caulking using any one of a plurality of bosses provided on the frame body. Therefore,
When recycling the process cartridge, the shaft can be attached by heat caulking an unused boss provided on the frame.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be specifically described with reference to the drawings.

[First Embodiment] FIG. 1 is a schematic explanatory view of the configuration of an image forming apparatus equipped with a process cartridge according to the present invention, and FIG. 2 is a schematic explanatory view of the configuration of a process cartridge.

As the order of description, first, the overall structure of the apparatus in which the process cartridge is mounted will be described, then the structure of each part of the image forming apparatus A and the process cartridge B will be described, and then the image carrier is rotatably supported. The mounting configuration of the shaft to be used 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 developer (hereinafter referred to as toner) image on the photosensitive drum which is an image carrier. Then, the recording medium 2 is conveyed by the conveying means 3 in synchronism with the formation of the toner image, and the toner image formed on the photosensitive drum in the image forming portion formed as a process cartridge B is transferred by the transfer means 4 to the recording medium. 2 and the recording medium 2
Is conveyed to the fixing unit 5, and the transferred toner image is fixed and discharged to the discharging unit 6.

As shown in FIG. 2, the process cartridge B constituting the image forming section rotates the photosensitive drum 7 to uniformly charge the surface thereof by the charging means 8 so that the light from the optical system 1 is emitted. The image is transferred to the photosensitive drum 7 via the exposure unit 9.
Is exposed to form a latent image, and the developing means 10 forms a toner image corresponding to the latent image to form a visible image. After the transfer means 4 transfers the toner image onto the recording medium 2, the cleaning means 11 removes the toner remaining on the photosensitive drum 7. Each component such as the photosensitive drum 7 is a resin toner frame body 12a that constitutes the housing 12.
It is housed in the cleaning frame 12b to form a cartridge.

[Image Forming Apparatus] The structure of each part of the image forming apparatus A will be described in the order of the optical system, the conveying means, the transfer means, the fixing means, and the cartridge mounting means.

(Optical System) The optical system 1 irradiates a light image on the photosensitive drum 7 by irradiating light on the basis of image information read from an external device or the like. As shown in FIG. A laser diode 1b, a polygon mirror 1c, a scanner motor 1d, and an imaging lens 1e are housed in the optical unit 1a of FIG.

When an image signal is given from an external device such as a computer or a word processor, the laser diode 1b emits light according to the image signal and illuminates the polygon mirror 1c as image light. The polygon mirror 1c is rotated at a high speed by a scanner motor 1d, and the image light reflected by the polygon mirror 1c is radiated to the rotating photosensitive drum 7 via the imaging lens 1e and the reflection mirror 1f, and the surface of the drum 7 is covered. It is selectively exposed to form a latent image according to image information.

(Recording Medium Conveying Means) Next, a conveying means 3 for conveying the recording medium 2 (for example, recording paper, OHP sheet, cloth or thin plate) has a mounting portion for the cassette 3a in the apparatus main body 13, The recording medium 2 in the cassette 3a mounted in the mounting portion is fed one by one from the top to the registration roller pair 3c1, 3c2 by the pickup roller 3b so that the registration roller pair 3c1, 3c2 may be synchronized with the image forming operation. The recording medium 2 is conveyed to the image transfer section. Then, the recording medium 2 after the image transfer is conveyed to the fixing means 5 by the conveying roller 3d and the guide plate 3e, and the recording medium 2 after fixing is discharged by the discharging roller 3f to the discharging portion 6 formed on the upper part of the apparatus.

(Transfer Means) The transfer means 4 is for transferring the toner image formed on the photosensitive drum 7 in the image forming section onto the recording medium 2. The transfer means 4 of this embodiment is as shown in FIG. , The transfer roller 4. That is, by pressing the recording medium 2 by the transfer roller 4 against the photosensitive drum 7 of the mounted process cartridge B, and applying a voltage having a polarity opposite to that of the toner image formed on the photosensitive drum 7 to the transfer roller 4, The toner on the photosensitive drum 7 is transferred to the recording medium 2.

(Fixing Means) The fixing means 5 fixes the toner image transferred to the recording medium 2 by applying a voltage to the transfer roller 4. Its configuration is as shown in FIG.
It is composed of a driving roller 5a that is driven to rotate, and a fixing roller 5c that has a heater 5b inside and that is driven to rotate by being pressed against the driving roller 5a. That is, when the recording medium 2 to which the toner image has been transferred in the image forming section passes between the driving roller 5a and the fixing roller 5c, pressure is applied by the pressing of both rollers 5a and 5c, and heat generation of the fixing roller 5c occurs. Heat is applied by the toner, and the toner on the recording medium 2 is fixed on the recording medium 2.

(Process Cartridge Mounting Unit) Inside the image forming apparatus A, a cartridge mounting unit for mounting the process cartridge B is provided. The process cartridge B is attached to and detached from the apparatus body 13 by opening the opening / closing cover 14. That is, an opening / closing cover 14 which can be opened and closed by a hinge 14a is attached to the upper part of the apparatus body 13. When the opening / closing cover 14 is opened, the device body
A cartridge mounting space is provided inside 13, and left and right guide members (not shown) are attached to the left and right wall surfaces of the opening / closing cover. A guide for inserting the process cartridge B is provided on the left and right guide members, and the process cartridge B is inserted along the guide to open and close the cover.
The process cartridge B is mounted on the image forming apparatus A by closing 14.

{Process Cartridge} Next, the structure of each part of the process cartridge B mounted in the image forming apparatus A will be described.

The process cartridge B is provided with an image carrier and at least one process means. Here, the process means includes, 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, and a cleaning means for cleaning the toner remaining on the surface of the image carrier. As shown in FIG. 2, in the process cartridge B of this embodiment, a charging unit 8, an exposing unit 9, a developing unit 10, and a cleaning unit 11 are arranged around an electrophotographic photosensitive drum 7 which is an image carrier. The toner frame body 12a and the cleaning frame body 12b are covered with a housing to be integrated with each other so that the apparatus body 13 can be attached and detached.

Next, the structure of each part of the process cartridge B will be described with reference to the photosensitive drum 7, the charging means 8, the exposing part 9, and the developing means.
The cleaning unit 11 and the cleaning unit 11 will be described in this order.

(Photosensitive Drum) The photosensitive drum 7 according to this embodiment is constructed by coating an organic photosensitive layer on the outer peripheral surface of a cylindrical drum base made of aluminum. This photosensitive drum 7 is rotatably attached to the frame, and by transmitting the driving force of the drive motor provided on the apparatus main body side to a flange gear fixed to one end of the photosensitive drum 7 in the longitudinal direction as described later, The photosensitive drum 7 is rotated in the direction of the arrow in FIG. 1 according to the image forming operation.

(Charging means) The charging means is for uniformly charging the surface of the photosensitive drum 7, and in the present embodiment, the charging roller 8 is rotatably attached to the frame, so-called contact charging. Method. The charging roller 8 has a metal roller shaft 8a provided with a conductive elastic layer, a high resistance elastic layer further provided thereon, and a protective film provided on the surface thereof. The conductive elastic layer is formed by dispersing carbon in an elastic rubber layer such as EPDM or NBR and has a function of guiding a bias voltage supplied to the roller shaft 8a. The high resistance elastic layer is made of urethane rubber or the like and contains a minute amount of conductive fine powder.
Even when the charging roller with high conductivity such as the pinhole is opposed, the leak current to the photosensitive drum 7 is limited to prevent the bias voltage from dropping sharply. The protective layer is made of N-methylmethoxylated nylon so that the plastic material of the conductive elastic layer or the elastic layer of high resistance does not touch the photosensitive drum 7 and deteriorate the surface of the photosensitive drum 7. To work.

The charging roller 8 is connected to the photosensitive drum 7
When the image is formed, the charging roller 8 rotates following the rotation of the photoconductor drum 7. At this time, the DC voltage and the AC voltage are superimposed and applied to the charging roller 8 to apply the DC voltage to the photoconductor drum 7. Charge the surface uniformly.

(Exposure Unit) The exposure unit 9 exposes the surface of the photosensitive drum 7 uniformly charged by the charging roller 8 with the optical image emitted from the optical system 1 to form an electrostatic latent image on the surface of the drum 7. And an opening 9 for guiding the optical image is provided on the upper surface of the cartridge frame to form an exposure section.

(Developing Means) The developing means 10, as shown in FIG. 2, contains toner in a toner frame 12a for containing toner, and the toner feeding member 10a for feeding the toner.
Is rotatably provided. A developing sleeve 10c has a non-rotating magnet 10b inside the opening of the toner frame 12a and forms a thin toner layer on the surface by rotating.
Are provided at a minute distance from the photosensitive drum 7.

The developing sleeve 10c is constructed by roughening the surface of an aluminum cylindrical member by sandblasting or the like, and applying a conductive paint in which a pigment is dispersed on the surface. A toner layer is formed on the surface of the developing sleeve 10c. When toner is formed, friction between the toner and the developing sleeve 10c provides sufficient triboelectric charge to develop the electrostatic latent image on the photosensitive drum 7. Further, a developing blade 10d is provided to regulate the toner layer thickness.

(Cleaning Means) Cleaning Means 11
As shown in FIG. 2, the configuration of the cleaning blade 11a contacts the surface of the photoconductor drum 7 to scrape off the toner remaining on the drum 7 and the cleaning blade 11a for scooping off the scraped toner. Located below 11a,
And a squishy sheet that is in weak contact with the surface of the photosensitive drum 7.
11b and a waste toner reservoir 11c for storing the scraped waste toner.

{Attachment Structure of Shaft for Supporting Photosensitive Drum} Next, referring to FIGS. 3 to 5, for a structure for attaching a shaft for rotatably supporting the photosensitive drum 7, which is a rotating body, to the frame body 12b. explain.

As shown in FIG. 3, the photosensitive drum 7 has a flange 15 and a flange gear 16 fixed to both ends in the longitudinal direction by adhesion or caulking, and the shaft 17 is fitted to the flange 15 and the flange gear 16, respectively. It is inserted and rotatably supported. The shaft 17 has a shaft portion 17a fitted into the flange 15 and the flange gear 16 and a flange portion 17b supported by the frame body 12b. The flange portion 17b has a flange portion 17b, as shown in FIG.
Two boss insertion holes 17b1 are provided.

On the other hand, a cleaning frame to which the shaft 17 is attached
As shown in FIG. 4, a plurality of (8 in this embodiment) bosses 18a to 18h are provided on the 12b, and when mounting the shaft 17, two bosses 18a, 18a are provided in the insertion hole 17b1. 18e is inserted and the bosses 18a and 18e are heat-crimped. As a result, the shaft 17 is fixed to the frame 12b, and the photosensitive drum 7 is rotatably supported by the shaft 17.

Next, when recycling the process cartridge B, the photosensitive drum 7 and the like are removed from the frame 12b, the toner and the like are cleaned, and the life parts are replaced and reassembled. At this time, the photosensitive drum 7 can be easily removed from the frame body 12b by cutting out the heat-crimped bosses 18a and 18e. In order to attach it to the frame body 12b again, unused bosses other than the cut-out bosses 18a and 18e, for example, bosses 18b and 18f as shown in FIG. Can be attached. In this embodiment, since the eight bosses are provided, the shaft 17 can be attached four times.

Therefore, it is not necessary to replace the frame body 12b with a new one at the time of recycling, the recycling efficiency is improved, and the number of parts is reduced because a screw stop or the like is not necessary, so that the cost can be reduced.

[Second Embodiment] In the above-described embodiment, the photosensitive drum 7 is exemplified as the rotating body, and the shaft 17 supporting the photosensitive drum 7 is used.
However, the rotating body is not limited to the photosensitive drum 7. For example, as shown in FIGS. 6 and 7, the shaft 19 for rotatably supporting the developing sleeve 10c may be similarly attached.

That is, the flange 20a and the flange gear 20b are fixed to both ends of the developing sleeve 10c in the longitudinal direction (outside of the gap roller 22 for ensuring the gap between the photosensitive drum 7 and the developing sleeve 10c), and the flange 20a and the flange gear 20b are fixed to the bearing portions 19a and 19a. Tsuba 19b
It is rotatably supported by a bearing 19 having. This bearing
As shown in FIG. 7, the collar portion 19 is attached when mounting the collar portion 19.
The two insertion holes 19b1 provided in b are the two bosses 21a and 21d of the plurality of bosses 21a to 21f provided in the toner frame 12a.
And bosses 21a and 21d are heat caulked. As a result, the bearing 19 is fixed to the frame 12a, and the developing sleeve
10c is rotatably supported.

At the time of recycling, the bosses 21a and 21d are cut off to remove the developing sleeve 10c from the frame body 12a, and to attach this, unused bosses other than the cut bosses 21a and 21d, for example, bosses 21b and 21e are used. The bearing 19 can be mounted by using it and heat crimping it.

[Other Embodiments] As a mounting structure of a shaft for rotatably supporting a rotating body, in addition to the photosensitive drum 7 and the developing sleeve 10c, for example, a toner feeding member 10a, a charging roller and the like are used as a frame body. The same can be done when supporting.

Further, the process cartridge B according to the present invention described above 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, 2 colors).
It can also be suitably applied to a cartridge that forms a color image, a three-color image, a full-color image, or the like.

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.

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 the 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 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
For example, an electrophotographic photosensitive member as an image carrier and at least one process 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 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 one in which the charging means, the developing means or the cleaning means and the electrophotographic photosensitive member are integrally made into a cartridge, 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 apparatus main body.

Further, in the above-described embodiment, the photosensitive drum 7 and the developing sleeve 10c are made into a cartridge, and an apparatus for forming an image by mounting this process cartridge is exemplified. However, the photosensitive drum 7 and the developing sleeve 10c are made into a cartridge. The present invention can be similarly applied to the image forming apparatus directly attached to the apparatus main body without doing so.

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

[0052]

As described above, according to the present invention, the shaft for rotatably supporting the rotating member on the frame body is attached by thermally caulking at least one of the plurality of bosses provided on the frame body. Since it is configured as above, it is not necessary to replace the frame with a new one at the time of recycling, the recycling process is simplified, the recycling efficiency is improved, and the number of parts is reduced because screws are not required and the cost is reduced. This has the effect of being able to achieve down.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram of a configuration of a process cartridge.

FIG. 3 is an explanatory cross-sectional view showing a supporting structure of a photosensitive drum.

FIG. 4 is a side view illustrating a supporting structure of a photosensitive drum.

FIG. 5 is an explanatory side view showing a support structure of a photosensitive drum during recycling.

FIG. 6 is an explanatory diagram showing a supporting structure of a developing sleeve.

FIG. 7 is an explanatory diagram showing a supporting structure of a developing sleeve.

FIG. 8 is an explanatory diagram of a support structure of an image carrier according to a conventional technique.

[Explanation of symbols]

A ... Image forming apparatus, B ... Process cartridge, 1 ... Optical system, 1a ... Optical unit, 1b ... Laser diode, 1c ... Polygon mirror, 1d ... Scanner motor,
1e ... Image forming lens, 1f ... Reflecting mirror, 2 ... Recording medium,
3 ... conveying means, 3a ... cassette, 3b ... pickup roller, 3c1, 3c2 ... registration roller, 3d ... conveying roller, 3e ... guide plate, 3f ... discharging roller, 4 ... transfer means, 5 ... fixing means, 5a ... driving roller 5b ... heater,
5c ... Fixing roller, 6 ... Discharging section, 7 ... Photosensitive drum,
8 ... Charging roller, 8a ... Roller shaft, 9 ... Exposure section, 10 ... Developing means, 10a ... Toner feeding member, 10b ... Magnet, 10c ... Developing sleeve, 10d ... Developing blade, 11 ... Cleaning means, 11a ... Cleaning blade, 11b ... Squeeze sheet, 11c ... Waste toner reservoir, 12 ... Housing, 12a ... Toner frame, 12b ... Cleaning frame, 13 ... Device body, 14 ...
Open / close cover, 14a ... Hinge, 15 ... Flange, 16 ... Flange gear, 17 ... Shaft, 17a ... Shaft part, 17b ... Collar part, 17b1 ... Insertion hole, 18a-18h ... Boss, 19 ... Shaft, 19a ... Shaft part, 19b ... Collar portion, 19b1 ... Insertion hole, 20a ... Flange, 20b ... Flange gear, 21a-21f ... Boss, 22 ... Gap roller

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G03G 21/10 6605-2H G03G 21/00 310

Claims (10)

[Claims] 1. A process cartridge mountable to a main body of an image forming apparatus, an image carrier, at least one process unit acting on the image carrier, and a frame body supporting the image carrier and the process unit. And a shaft for rotatably supporting the rotating member on the frame,
A process cartridge, characterized in that at least one of a plurality of bosses provided on the frame is attached by heat caulking. 2. The process cartridge according to claim 1, wherein the rotating body is an image carrier. 3. The process cartridge according to claim 1, wherein the rotating body is a developing sleeve which constitutes a process means. 4. The process cartridge comprises a charging means, a developing means or a cleaning means as the process means, and an electrophotographic photosensitive member as the image carrier, which are integrally formed into a cartridge, and the cartridge is formed into an image forming apparatus main body. The process cartridge according to claim 1, wherein the process cartridge is removable. 5. The process cartridge is an image forming apparatus in which at least one of a charging unit, a developing unit, and a cleaning unit as the process unit and an electrophotographic photosensitive member as the image carrier are integrally formed into a cartridge. The process cartridge according to claim 1, wherein the process cartridge is removable from the main body. 6. The process cartridge is configured such that at least a developing unit as the process unit and an electrophotographic photosensitive member as the image carrier are integrally made into a cartridge so as to be attachable to and detachable from the main body of the image forming apparatus. The process cartridge according to claim 1, which is a product. 7. An image forming apparatus for mounting a process cartridge to record an image on a recording medium, comprising: an image carrier, at least one process unit acting on the image carrier, the image carrier and the process unit. A process cartridge having a supporting frame and a shaft for rotatably supporting a rotating member on the frame, which is attached by thermally caulking at least one of a plurality of bosses provided on the frame. An image forming apparatus comprising: a mounting unit for mounting a recording medium; and a transporting unit for transporting a recording medium. 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.