JPH08160838A - Process cartridge and image forming device - Google Patents

Abstract

PURPOSE: To easily and surely load/unload a process cartridge in a device main body by setting a force for pressing the shutter means of the process cartridge in its closing direction to a particular size. CONSTITUTION: A twisting coil spring 17c is attached to the rotary shaft part of a shutter arm part 17a and this presses a shutter member 17b always in its closing direction. When an open/close cover 18 is opened, the thrust pressure applied by cartridge pressing parts 20a and 20b is released. By means of the energizing force of the spring 17c, the shutter member 17b pushes a shutter receiving base 19 and by means of its reactive force, the loading direction front side of the process cartridge B is rotated and moved with a projection 21 as a fulcrum. Thus, the process cartridge B is raised from its normal loading position to its second position and a guide projection part 16b is detached upward from the U groove 16c of a guide part 16a. In this manner, the pressing force of the spring 17c is set.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a copying machine, a laser beam printer and a facsimile machine, and a process cartridge detachably mountable to the image forming apparatus.

[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, which is an electrophotographic photosensitive member uniformly charged by a charger, to form a latent image. The image is visualized with a developer (hereinafter referred to as "toner"), and the image by the toner is transferred to a recording medium to perform image recording. In such a device, the maintenance of each member was performed by a professional service person.

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 refill the toner and replace parts of the image bearing member that have reached the end of life by loading the cartridge into the main body of the apparatus, facilitating maintenance. What has been done has been put to practical use.

In such a process cartridge, guide protrusions projecting outward are provided on both side walls of the process cartridge, and the guide protrusions are provided on the left and right inner walls of the cartridge mounting space of the apparatus main body. Some are installed by inserting along. At this time, since it is necessary to position and mount the process cartridge at a predetermined position of the image forming apparatus main body, a U groove is provided at the end of the guide portion, and the guide protrusion of the inserted process cartridge is dropped into the U groove. It is positioned in this way.

[0005]

However, when the guide protrusion of the process cartridge is dropped into the U groove of the apparatus main body and positioned as described above, when the process cartridge is taken out from the apparatus main body, the process cartridge is first removed. It is necessary to lift it up a little and remove the guide protrusion from the U groove, and then pull it out from the device body and take it out. At this time, if not carefully done, the cartridge is apt to be caught in the U groove, and it takes time and effort to take out the process cartridge from the apparatus main body.

The present invention is to solve the above-mentioned conventional problems, and an object thereof is to provide a process cartridge and an image forming apparatus which can be easily and surely attached to and detached from the main body of the image forming apparatus. To do.

[0007]

A typical configuration according to the present invention for achieving the above object is to provide a process cartridge detachable from an image forming apparatus main body with an image carrier.
At least one process means acting on the image carrier, a frame supporting the image carrier and the process means,
And a shutter unit that can open and close a part of the frame and is always biased in the closing direction. The force for biasing the shutter unit in the closing direction is applied to the process cartridge of the image forming apparatus main body. It is characterized in that the process cartridge is set to a size such that the process cartridge is moved from the regular mounting position to the second position when the force for fixing to the regular mounting position is released.

An image forming apparatus having a mounting means for mounting the process cartridge is configured.

When the process cartridge is mounted on the main body of the image forming apparatus, the shutter arm supporting the shutter member is brought into contact with a part of the main body of the image forming apparatus so that the shutter member is opened. It is characterized in that it is fixed in a regular mounting position by being dropped into the U groove of the image forming apparatus main body and pressed from above.

[0010]

In the above construction, when the process cartridge is released from the mounting state when the process cartridge is mounted on the main body of the image forming apparatus, the process cartridge is moved from the mounting position to the second position, for example, upward by the biasing force of the shutter means. As a result, the guide protrusion comes out of the U-shaped groove in the main body of the apparatus.

Therefore, the process cartridge can be easily taken out from the apparatus main body by simply pulling it out.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described with reference to the drawings.

[First Embodiment] A process cartridge and an image forming apparatus according to the first embodiment will be described with reference to FIGS. 1 to 3. 1 is an explanatory diagram of the configuration of the image forming apparatus, FIG. 2 is an explanatory diagram of the configuration of the process cartridge, and FIG. 3 is an explanatory diagram of a state in which the process cartridge is mounted.

Here, as the order of the description, the overall structure of the image forming apparatus A and the process cartridge B will be described first, and then the structures of the shutter means and the cartridge mounting means will be described.

{Overall Configuration} This image forming apparatus A is shown in FIG.
As shown in FIG. 3, the electrophotographic image forming apparatus irradiates a laser light image based on image information from the optical system 1 to form a toner image on an electrophotographic photosensitive member which is an image carrier. Then, in synchronization with the formation of the toner image, the recording medium 2 is fed from the paper feed cassette 3a to the pickup roller 3b and the feeding roller 3
c, a pair of conveyance rollers 3d, a pair of registration rollers 3e, and the like, and a toner image formed on the photosensitive drum is transferred as a transfer unit in an image forming unit that is transferred as a process cartridge B into a cartridge. The voltage is applied to the roller 4 to transfer it to the recording medium 2, and the recording medium 2 is guided by the guide plate 3f and conveyed to the fixing means. The fixing unit 5 is composed of a driving roller 5a and a fixing roller 5b having a built-in heater, and applies heat and pressure to the recording medium 2 passing therethrough to fix the transferred toner image. Then, the recording medium 2 is conveyed by the pair of discharge rollers 3g and 3h, and is discharged to the discharge unit 6 through the reverse transport path. The image forming apparatus A can also be manually fed by the manual feed tray 3i and the rollers 3j.

On the other hand, in the process cartridge B forming the image forming portion, as shown in FIG. 2, a photosensitive drum 7 which is an electrophotographic photosensitive member having a photosensitive layer is rotated, and its surface is charged by a charging means. The roller 8 is uniformly charged by applying a voltage, and the optical image from the optical system 1 is exposed on the photosensitive drum 7 through the opening 9 to form a latent image.
It is configured to be developed by.

The developing means 10 sends out the toner in the toner storage portion 10a by the sending member 10b, rotates the developing roller 10d which is the developing rotary member having the fixed magnet 10c built therein, and causes the developing blade 10e to apply the triboelectric charge. The applied toner layer is formed on the surface of the developing roller 10d, and the toner is transferred to the photosensitive drum 7 in accordance with the latent image to form a toner image and visualize it. Then, after a voltage having a polarity opposite to that of the toner image is applied to the transfer roller 4 to transfer the toner image to the recording medium 2, the cleaning blade 11a scrapes off the toner remaining on the photosensitive drum 7, and the rake sheet 11b scoops it. Cleaning means 11 for collecting and collecting in the waste toner reservoir 11c
Is configured to remove the residual toner on the photoconductor drum 7.

Each member such as the photoconductor drum 7 constitutes a developing unit by welding a toner frame 12 for containing toner and a developing frame 13 for holding a developing member such as the developing roller 10d. , The photosensitive drum 7 on the cleaning frame 14
The cartridge is housed in a cartridge frame constituted by being combined with a cleaning unit having the cleaning means 11 and the like attached thereto to be made into a cartridge, which is detachably attached to the cartridge attaching means 16 provided in the apparatus main body 15.

In the process cartridge B, an opening is provided in a part of the cleaning frame body 14, and the photosensitive drum 7 can be exposed through the opening. A shutter means 17 is provided to open and close the opening to protect the photosensitive drum 7.

{Structure of Shutter Means and Mounting Means} Next, the structures of the cartridge mounting means 16 and the shutter means 17 will be described.

As shown in FIG. 3, when the opening / closing cover 18 is opened about the shaft 18a, the cartridge mounting means 16 is moved forward (to the left in FIG. 3) on the left and right inner side surfaces of the cartridge mounting space in the apparatus main body. Cartridge mounting guide portions 16a that are inclined obliquely downward are provided facing each other (FIG. 3 shows only one side surface).

On the other hand, on both sides in the longitudinal direction of the process cartridge B, guide projections 16b are formed so as to project outward from a portion coaxial with the bearing of the photosensitive drum 7, and the guide projections 16 are formed.
The process cartridge B is inserted into the apparatus main body 15 by inserting b along the guide portion 16a of the apparatus main body.

Further, a U groove 16c is continuously formed at the front end of the guide portion 16a, and the guide protrusion 16b of the inserted process cartridge B is dropped into the U groove 16c for positioning. There is. Then, when the guide protrusion 16b falls into the U groove and the process cartridge B is mounted in the proper position, a drum gear (not shown) attached to the longitudinal end of the photosensitive drum 7 is provided in the apparatus main body 15. The drive force is transmitted to the photosensitive drum 7 by meshing with a drive transmission gear (not shown).

In the shutter means 17, shutter arm portions 17a are rotatably attached to both sides in the longitudinal direction of the process cartridge B, and a shutter member 17b is attached to a rotary end portion of the shutter arm portion 17a. By rotating the shutter arm portion 17a, the shutter member 17b opens and closes the opening of the cartridge frame. A torsion coil spring 17c is attached to the rotary shaft portion of the shutter arm portion 17a, which is locked by the shutter arm portion 17a and the projection 17d to urge the shutter member 17b in a direction to be always closed. .

An arm link (not shown) is connected to the shutter arm portion 17a, and when the process cartridge B is inserted into or removed from the apparatus main body 15,
The arm link comes into contact with the guide portion 16a of the apparatus body 15. Thus, when the cartridge B is inserted, the shutter arm 17a is rotated against the bias of the spring 17c to open the shutter member 17b, and when the cartridge B is pulled out, the shutter arm 17b is biased by the spring 17c. The shutter member 17b is closed by rotating the shutter member 17b in the direction.

Therefore, as shown in FIG. 3, when the process cartridge B is inserted into the apparatus main body 15, the shutter member 17b opens in the forward direction in conjunction with this. When the process cartridge B is inserted into the guide portion 16a, the tip of the shutter member 17b comes into contact with the upper portion of the shutter pedestal 19 fixedly provided in the apparatus body, and the elastic force of the spring 17c (shutter) is released. The force for closing the member) is applied to the shutter pedestal 19, and the reaction force lifts the front side of the process cartridge B in the mounting direction.

When the opening / closing cover 18 is closed in the above state, FIG.
As shown in FIG. 7, the process cartridge B is pressed downward by the cartridge pressing portions 20a and 20b provided on the inner top surface of the opening / closing cover 18, and the guide protrusion 16b of the cartridge B is pressed.
Is fitted into the positioning U groove 16c, and the cartridge B is mounted in the regular mounting position.

When the process cartridge B is taken out from the apparatus main body 15, when the opening / closing cover 18 is opened, the pressing of the cartridge pressing portions 20a and 20b is released, and the shutter member 17b receives the shutter by the biasing force of the spring 17c of the shutter means 17. The base 19 is pushed, and the reaction force causes the front side in the mounting direction of the process cartridge B to rotate and move around the protrusion 21 as a fulcrum and lifted from the regular mounting position to the second position (state of FIG. 3), and the guide protrusion. 16b is disengaged upward from the U groove 16c. As described above, in the present embodiment, the biasing force of the spring 17c is set so that the process cartridge B can move from the regular mounting position to the second position when the opening / closing cover 18 is opened. .

Therefore, when the user takes out the process cartridge B, the user can easily open the opening / closing cover 18 and pull the process cartridge B forward, and easily from the apparatus main body 15 and the guide protrusion 16b into the U groove 16c. It can be taken out without being caught.

When the process cartridge B is installed, as shown in FIG. 1, the shutter member 17b
Since the sheet is mounted on the shutter mount 19 and is surely opened, the recording medium 2 passing below the process cartridge B is not caught by the shutter member 17b and jammed.

[Second Embodiment] Next, a second embodiment of the structure for moving the process cartridge by the shutter means will be described.
This will be described with reference to FIGS. 4 and 5. 4 is a schematic explanatory view of the image forming apparatus when the process cartridge is completely mounted, and FIG. 5 is a schematic explanatory view of the image forming apparatus when the process cartridge is attached and detached. Further, members having the same functions as those in the first embodiment described above are designated by the same reference numerals, and duplicate description will be omitted.

Process cartridge B according to this embodiment
In the shutter means 22, the first shutter arm portion 22a is rotatably attached to both sides of the process cartridge B in the longitudinal direction, the second shutter arm portion 22b is connected to the first shutter arm portion 22a, and the second shutter arm portion 22a is further connected. A shutter member 22c is connected to the portion 22b. Then, a torsion coil spring 22d is attached to the rotary shaft of the first shutter arm portion 22a and urges the shutter member 22c in a direction to always close it.

This process cartridge B is attached to the apparatus main body 15
The first shutter arm portion 22a is inserted into the main body 15 of the apparatus.
When the cartridge B is inserted and is supported by the projection 24 provided on the upper frame body 23 of the
Process cartridge B via shutter arm 22b
Slide open the bottom of the cartridge in the direction opposite to the cartridge insertion direction. When the opening / closing cover 18 is closed with the cartridge B inserted to a certain position, the cartridge pressing portion 25 attached to the opening / closing cover 18 pushes the cartridge B further into the apparatus main body 15 and the guide protrusion 16b of the cartridge B is released. The process cartridge B is fitted in the cartridge positioning U groove 16c and mounted in the proper position (state of FIG. 4).

When the process cartridge B is taken out from the apparatus main body 15, when the opening / closing cover 18 is opened, the pressing of the cartridge pressing portion 25 is released, and the spring 22d of the shutter means 22 is released.
The shutter member 22c pushes the upper frame body 23 by the urging force of the process cartridge B, and the process cartridge B receives a reaction force in the opening direction of the apparatus main body with the protrusion 24 as a fulcrum, and the process cartridge B moves from the normal mounting position to
Lifted to the position (state of Fig. 5), guide protrusion 16b
Comes off from the U groove 16c. As described above, also in the present embodiment, when the opening / closing cover 18 is opened, the biasing force of the spring 22d is set so that the process cartridge B can move from the regular mounting position to the second position. There is.

Thus, when the user takes out the process cartridge B, the user can easily open the opening / closing cover 18 and pull the process cartridge B toward the front side of the apparatus main body 15 and the guide protrusion 16b into the U groove 16c. It can be taken out without being caught.

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

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 bearing member is not limited to the above-mentioned photosensitive drum, but includes, for example, the following. 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 constitution 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 constitution 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
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, 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 released from the mounting position by the urging force of the shutter means when the process cartridge is released from the mounting state in the main body of the image forming apparatus. Since it is configured to move to a position, for example, upward, the guide protrusion of the process cartridge is set to U of the apparatus main body.
When the process cartridge is mounted by dropping it in the groove and the process cartridge is unfixed when the cartridge is taken out, the guide protrusion comes to be disengaged from the U groove in the apparatus main body. Therefore, the process cartridge can be easily taken out from the main body of the apparatus by simply pulling it out, and the guide protrusion can be surely taken out without being caught in the U groove.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a configuration of an image forming apparatus.

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

FIG. 3 is an explanatory view of a state in which a process cartridge is mounted.

FIG. 4 is a schematic explanatory diagram of an image forming apparatus when a process cartridge according to a second exemplary embodiment is completely mounted.

FIG. 5 is a schematic explanatory diagram of the image forming apparatus when the process cartridge according to the second embodiment is attached and detached.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Optical system 2 ... Recording medium 3 ... Conveying means 4 ... Transfer roller 5 ... Fixing means 7 ... Photosensitive drum 8 ... Charging roller 10 ... Developing means 11 ... Cleaning means 15 ... Device body 16 ... Cartridge mounting means 17 ... Shutter means 18 ... Open / close cover 19 ... Shutter cradle 25 ... Cartridge holder

Claims (11)

[Claims] 1. A process cartridge attachable to and detachable from 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. A shutter unit that can open and close a part of the frame body and is always biased in a closing direction, and a force that biases the shutter unit in a closing direction is applied to the main body of the image forming apparatus. The process cartridge is sized to move the process cartridge from the regular mounting position to the second position when the force for fixing the process cartridge to the regular mounting position is released. 2. The process cartridge according to claim 1, wherein the shutter means is for shielding the image carrier. 3. 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 in the main body of the image forming apparatus. The process cartridge according to claim 1, wherein the process cartridge is removable. 4. 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. 5. 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. 6. An image forming apparatus for forming an image on a recording medium, wherein a process cartridge is attachable / detachable, an image carrier, at least one process unit acting on the image carrier, the image carrier, and It has a frame body that supports the process means, and shutter means that can open and close a part of the frame body and is always biased in the closing direction, and the force that biases the shutter means in the closing direction is For mounting the process cartridge set to a size that moves the process cartridge from the regular mounting position to the second position when the force for fixing the process cartridge to the regular mounting position of the image forming apparatus main body is released. A mounting means; a transfer means for transferring the image formed on the image carrier to a recording medium; and a transporting means for transporting the recording medium. An image forming apparatus symptoms. 7. The shutter means is configured such that, when the process cartridge is mounted on the image forming apparatus main body, a shutter arm portion supporting the shutter member abuts a part of the image forming apparatus main body to open the shutter member. The image forming apparatus according to claim 6, which is characterized in that. 8. The mounting means drops the guide protrusion of the process cartridge into a U groove of the image forming apparatus main body,
7. The image forming apparatus according to claim 6, wherein the image forming apparatus is fixed to a regular mounting position by pressing it from above. 9. The image forming apparatus according to claim 8, wherein the urging force of the shutter means acts in a direction to move the guide protrusion upward when the process cartridge is mounted. 10. The image forming apparatus according to claim 8, wherein the second position is a position where the guide protrusion of the process cartridge comes out of the U groove of the image forming apparatus main body. 11. The image forming apparatus according to claim 6, wherein the image forming apparatus is an electrophotographic copying machine, a laser beam printer, or a facsimile machine.