JPH0643703A - Image forming device capable of fitting process cartridge - Google Patents

Abstract

PURPOSE:To attain accurate positioning with the principal part of an optical system requiring positional precision with a process cartridge by fitting a positioning member provided on a lower part housing case into the rotational center shaft of a photosensitive body. CONSTITUTION:When an opening/closing cover 8 is closed, the rotational center shaft 12a of a drum on both end parts of the photosensitive drum 12 is fitted into the groove part of a positioning block 18a arranged on a lower part main body. Moreover, a part of the frame body of the process cartridge 9 buts against the a butting block 19 positioning/supporting the frame body of the cartridge 9, to prevent the frame body of the process cartridge 9 from being rotated. Further, a transfer guiding plate 4 is fixed on the positioning block 18a, and an upper housing case is closed to automatically guarantee the equivalent positional precision of the photosensitive drum 12 and the transfer guiding plate 4, as well.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using a process cartridge in which two or more image forming means such as a photoconductor, a developing device, a cleaning device, and a charging device are integrated and supported by a supporting means. The present invention relates to an image forming apparatus such as a facsimile, a personal computer, a copying machine, and a word processor for outputting images such as characters and drawings on a recording material.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus using a process cartridge, the main body of the apparatus can be opened and closed for facilitating the attachment and detachment of the process cartridge to the main body of the apparatus, and the process cartridge is attached to the upper casing to cover the same. The device is a type that can be closed and stored in the main body of the device.

In such an apparatus for positioning and arranging the process cartridge in the upper casing, if the cartridge is arranged in the upper casing together with the main part of the optical system, the weight of the upper casing increases and The supporting mechanism becomes large, and the vibration of the opening and closing motion further distorts the optical system to make it impossible to perform scanning unevenness and exposure of a clear image, and to cause adverse effects such as toner scattering from the cartridge.

An object of the present invention is to provide an image forming apparatus which does not cause various problems that are likely to occur when the conventional process cartridge is positioned and disposed in the upper casing.

[0005]

An image forming apparatus of the present invention supports an upper casing and a lower casing in an openable and closable manner, and supports the cartridge in the upper casing for facilitating attachment and detachment of a process cartridge. On the other hand, the main part of the optical system is provided in the lower housing. The positioning of the process cartridge and the optical system is performed by fitting the rotation center axis of the means for supporting the photosensitive member of the cartridge into a bearing member provided on the lower housing for receiving the rotation center axis. Is.

The rotation center axis of the photoreceptor is the rotation center axis of the drum when the photoreceptor is a drum, and the rotation center axis of the roller that supports the belt when the photoreceptor is a drum.
Further, the process cartridge may be one that integrally supports two or more means used for image formation, and for example, a combination of a photoconductor and a developing device, a photoconductor and a cleaning device, a photoconductor and a developing device and a cleaning device, and the like. There is.

[0007]

EXAMPLES The present invention will be described below with reference to examples. The illustrated apparatus scans a laser beam on a photoconductor to form an image.

1 and 2 are sectional views of an apparatus to which the present invention is applied. 2 shows a state in which the main body of the device shown in FIG. 1 is opened. In FIG. 1, a laser scanner 14 exposes an image signal on the photosensitive drum 12. The photosensitive drum 12 rotates in the direction of the arrow, and the corona charger 10 uniformly charges the photosensitive drum 12. The electrostatic latent image formed by exposing the uniformly charged photosensitive drum to light image by the laser scanner 14 is developed with the toner of the developing device 11. The photosensitive drum, the developing device, the cleaning device 13,
The charger is formed integrally with the frame and is the process cartridge 9
Are configured.

The transfer material 1 is fed to the surface of the drum 12 through the transfer guide plate 4 by the paper feed roller 2 and the register roller 3, and the toner image on the drum is transferred by the transfer charger 5. After that, the transfer material is separated from the drum and sent to the fixing device 6. The toner on the transfer material is fixed by the fixing device 6, and the transfer material is discharged by a paper discharge roller 7 to a tray on an opening / closing cover 8 which is part of the upper housing B. On the other hand, the toner remaining on the photosensitive drum 12 without being transferred is collected by the cleaning device 13.

In the figure, reference numeral 15 is a pre-exposure lamp, 16 is a hinge that is the center of rotation of the opening / closing cover 8, 17 is a spring for pressing the process cartridge 9 downward, and 18 is both end shafts 12a and 12b of the photosensitive drum 12. A positioning block 19 for engaging and holding is a butting block 19 for stopping the rotation of the process cartridge 9.

As shown in FIG. 2, the device of the present invention having the above-mentioned structure is as follows.
The opening / closing cover 8 as the upper housing and the lower housing A are separably joined by a hinge 16, and the opening / closing cover pivots upward around the hinge 16. The opening / closing cover is provided with a paper discharge roller 7, a pre-exposure lamp 15, a process cartridge 9, a guide 9a for receiving the cartridge, a spring 17 and the like. Further, a paper feed roller 2, a registration roller 3, a transfer guide plate 4, a fixing device 6, a laser scanner 14 which constitutes a main part of an optical system, a positioning block 18, an abutment block 19 and the like are arranged in the lower housing. . The cartridge 9 may be attached or detached in the rotation axis direction of the drum 12.

In the state of FIG. 2, the process cartridge 9
The spring is pressed downward by the spring 17 while being simply placed on the guide 9a inside the opening / closing cover 8 and is kept in a state in which it cannot be easily removed from the guide 9a by a stopper (not shown). In this state, if a force is applied upward against the force of the spring 17, the spring 17 is easily lifted.

Next, when the opening / closing cover 8 is closed (FIG. 1), the rotation center shaft 1 of the drum on both ends of the photosensitive drum 12 is closed.
2a (FIG. 4) fits into the groove of the positioning block 18a arranged on the lower body. Further, a part of the frame body of the process cartridge 9 abuts on the butting block 19 for positioning and supporting the frame body of the cartridge, and the process cartridge 9
As a result, it plays a role of preventing the frame body from rotating. Further, the transfer guide plate 4 is fixed to the positioning block 18a, and the photosensitive drum 1 is closed by closing the upper casing.
The relative positional accuracy between the transfer guide plate 2 and the transfer guide plate 4 is also automatically guaranteed.

FIG. 5 is a perspective view of the process cartridge as seen from below. In the figure, 12b is a gear for receiving a drive from the main body, which is fixed to the end of the photosensitive drum 12 integrally with the drum.

FIG. 6 shows a drive mechanism for the drum 12. The drive gear C provided in the lower housing A meshes with the gear 12b as shown in the drawing, so that the drive from the lower housing is performed by the drum 12. Be transmitted to.

Next, the image forming apparatus shown in FIG. 7 has a reflection mirror 14a in the upper housing in addition to the scanner in the lower housing A as optical means.

The reflection mirror 14a is fixed to the mirror holder 14c, and as shown in FIG.
Both ends of 4c are hooks 14 at the opening of the side wall of the opening / closing cover.
It is held by being engaged with d and is urged downward from above by a pressing leaf spring 14b fixed to the upper casing.

On the main body side, 14e is a mirror pedestal in which the lower surfaces of both ends of the mirror holder 14c are abutted against the slopes and positioned as shown in FIG. Reference numeral 14f denotes a scanner pedestal on which the laser scanner 14 is mounted and positioned, and is integrally molded together with the drum bearing pedestal 18b and the mirror pedestal from a reinforced plastic made of glass-filled polycarbonate or the like to ensure dimensional accuracy and mechanical strength. It is a frame structure. FIG. 9 shows a perspective view of the device when the upper housing is opened.

With the above construction, when the opening / closing cover 8 is in the closed state, the laser scanner 14 as a light source, the registration roller pair 3 which is a key for sheet conveyance, the photosensitive drum 12, and the reflection mirror 1 are provided.
Not only can the 4a be positioned integrally with the lower housing with high dimensional accuracy, but vibration can be extremely reduced by sufficiently increasing the mechanical strength of the integrated frame.

In FIG. 7, the arrow C indicates the loading direction of the process cartridge. FIG. 8 is a sectional view of the apparatus in a state in which the upper casing is closed and an image is formed,
FIG. 11 shows a partial side view of the 0-reflecting mirror 14a immediately before being positioned by the mirror pedestal 14e.

[0021]

As described above, by fitting the positioning member provided in the lower housing with the rotation center shaft of the photosensitive member, accurate positioning can be performed with the main part of the optical system which requires positional accuracy with the process cartridge. It has become possible. Furthermore, a transfer guide plate,
The transfer charger and the like can be positioned automatically at the same time, but they may be provided if necessary. Also, since the main part of the optical system is not provided in the upper housing, the structure for supporting the rotation of the housing may be simple, and it is possible to provide an image forming apparatus that is light and easy to operate for the user. It was

Even in the apparatus having the reflecting mirror shown in FIG. 7, when the opening / closing cover is simplified as much as possible and the process cartridge and the reflecting mirror incorporated in the opening / closing cover are closed without increasing the dimensional accuracy, Correctly positioned on the lower housing side. Further, since the laser scanner and the reflection mirror as the light source, the registration roller pair, and the image forming means such as the photosensitive drum of the process cartridge are substantially integrally coupled on the lower housing side, the positioning can be performed with high accuracy. There is an effect that the image quality can be maintained extremely good.

[Brief description of drawings]

FIG. 1 is a sectional view of an apparatus showing an embodiment of the present invention.

2 is a cross-sectional view of the device shown in FIG. 1 in a state in which an opening / closing cover is opened.

FIG. 3 is a partial side view of positioning means.

FIG. 4 is a plan view of the positioning unit shown in FIG.

FIG. 5 is a perspective view of the process cartridge as seen from below.

FIG. 6 is a perspective view of a drive mechanism.

FIG. 7 is a cross-sectional view of an apparatus having a reflection mirror.

FIG. 8 is a cross-sectional view of an apparatus having a reflection mirror.

9 is a perspective view of the apparatus shown in FIG. 7 when the upper housing is opened.

FIG. 10 is a partial side view showing a positioning state of a reflection mirror.

FIG. 11 is a partial side view showing a positioning state of a reflection mirror.

[Explanation of reference numerals] A lower casing B upper casing 9 process cartridge 9a process cartridge guide 12 photosensitive drum 12a rotation center axis 14a reflection mirror 14e mirror cradle 18a, 18b positioning block

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[Procedure amendment]

[Submission date] December 18, 1991

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Image forming apparatus to which process cartridge can be attached

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus in which a process cartridge integrally having an image bearing member and an operating means acting on the image bearing member is detachable.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus using a process cartridge, the main body of the apparatus can be opened / closed in order to facilitate the attachment / detachment of the process cartridge to / from the main body of the apparatus. A type in which the housing is closed and the process cartridge is housed in the main body of the apparatus has been realized.

However, in such a configuration in which the apparatus main body is opened and the process cartridge is attached and detached, it is difficult to accurately position the process cartridge with respect to the apparatus main body in a recordable state in which the apparatus main body is closed.

An object of the present invention is to provide an image forming apparatus capable of efficiently positioning the process cartridge with respect to the apparatus main body.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an image forming apparatus in which a process cartridge integrally having an image carrier and an image forming unit acting on the image carrier is detachable. And a first housing having a mounting means for mounting the process cartridge and movably supporting the process cartridge, and being capable of being opened relatively to the first housing and moving to the first housing. A second casing having a positioning means for positioning the rotation center of the image carrier provided in the process cartridge supported so as to be possible, and provided in the process cartridge provided in the process cartridge. The image forming apparatus is characterized in that the rotation center of the image carrier is positioned and mounted on the positioning means.

[0006]

EXAMPLES The present invention will be described below with reference to examples.

In the embodiment described below, the upper case is arranged so as to be openable and closable with respect to the lower case, the process cartridge is installed in the upper case, and is used with the upper case closed. In a possible image forming apparatus, the positioning of the process cartridge with respect to the lower housing is performed by the rotation center axis of the means for supporting the photosensitive member of the process cartridge and the central bearing member provided in the lower housing. It is a forming device. Furthermore, in an image forming apparatus capable of mounting a process cartridge, the upper housing is arranged to be openable and closable with respect to the lower housing, the upper housing is loaded with the process cartridge, and the upper housing is used in a closed state. The main part of the optical means is provided in the lower housing, the process cartridge and a part of the optical means are provided in the upper housing, and the positioning of the process cartridge with respect to the lower housing is performed by the rotation center of the means for supporting the photoconductor of the process cartridge. The shaft and the central bearing member provided on the lower housing are used to position the optical means of the upper housing with respect to the lower housing. The image forming apparatus is capable of mounting a process cartridge by abutting on a locking member provided.

Thus, the image forming apparatus described below is
The upper case and the lower case are supported so that they can be opened and closed, and the supporting means for this cartridge is provided in the upper case to facilitate the attachment and detachment of the process cartridge, while the main part of the optical system is provided in the lower case. is there. The positioning of the process cartridge and the optical system is performed by fitting the rotation center axis of the means for supporting the photosensitive member of the cartridge into a bearing member provided on the lower housing for receiving the rotation center axis. Is. The rotation center axis of the photoconductor is
When the photoconductor is a drum, it is the rotation center axis of the drum, and when it is a belt, it is the rotation center axis of the roller that supports the belt. Further, the process cartridge may be one that integrally supports two or more means used for image formation,
For example, there are combinations of a photoconductor and a developing device, a photoconductor and a cleaning device, a photoconductor, a developing device, and a cleaning device.

Now, the following exemplary device forms an image by scanning a laser beam on a photoconductor.

1 and 2 are sectional views of an apparatus to which the present invention is applied. 2 shows a state in which the main body of the device shown in FIG. 1 is opened. In FIG. 1, a laser scanner 14 exposes an image signal on the photosensitive drum 12. The photosensitive drum 12 rotates in the direction of the arrow, and the corona charger 10 uniformly charges the photosensitive drum 12. The electrostatic latent image formed by exposing the uniformly charged photosensitive drum to light image by the laser scanner 14 is developed with the toner of the developing device 11. The photosensitive drum, the developing device, the cleaning device 13,
The charger is formed integrally with the frame and is the process cartridge 9
Are configured.

The transfer material 1 is fed to the surface of the drum 12 through the transfer guide plate 4 by the paper feed roller 2 and the register roller 3, and the toner image on the drum is transferred by the transfer charger 5. After that, the transfer material is separated from the drum and sent to the fixing device 6. The toner on the transfer material is fixed by the fixing device 6, and the transfer material is discharged by a paper discharge roller 7 to a tray on an opening / closing cover 8 which is part of the upper housing B. On the other hand, the toner remaining on the photosensitive drum 12 without being transferred is collected by the cleaning device 13.

In the figure, 15 is a pre-exposure lamp, 16 is a hinge which is the center of rotation of the opening / closing cover 8, 17 is a spring for pressing the process cartridge 9 downward, and 18 is both end shafts 12a and 12b of the photosensitive drum 12. A positioning block 19 for engaging and holding is a butting block 19 for stopping the rotation of the process cartridge 9.

As shown in FIG. 2, the device of the present invention having the above structure is
The opening / closing cover 8 as the upper housing and the lower housing A are separably joined by a hinge 16, and the opening / closing cover pivots upward around the hinge 16. The opening / closing cover is provided with a paper discharge roller 7, a pre-exposure lamp 15, a process cartridge 9, a guide 9a for receiving the cartridge, a spring 17 and the like. Further, a paper feed roller 2, a registration roller 3, a transfer guide plate 4, a fixing device 6, a laser scanner 14 which constitutes a main part of an optical system, a positioning block 18, an abutment block 19 and the like are arranged in the lower housing. . The cartridge 9 may be attached or detached in the rotation axis direction of the drum 12.

In the state of FIG. 2, the process cartridge 9
The spring is pressed downward by the spring 17 while being simply placed on the guide 9a inside the opening / closing cover 8 and is kept in a state in which it cannot be easily removed from the guide 9a by a stopper (not shown). In this state, if a force is applied upward against the force of the spring 17, the spring 17 is easily lifted.

Next, when the opening / closing cover 8 is closed (FIG. 1), the rotation center shaft 1 of the drum at both ends of the photosensitive drum 12 is closed.
2a (FIG. 4) fits into the groove of the positioning block 18a arranged on the lower body. Further, a part of the frame body of the process cartridge 9 abuts on the butting block 19 for positioning and supporting the frame body of the cartridge, and the process cartridge 9
As a result, it plays a role of preventing the frame body from rotating. Further, the transfer guide plate 4 is fixed to the positioning block 18a, and the photosensitive drum 1 is closed by closing the upper casing.
The relative positional accuracy between the transfer guide plate 2 and the transfer guide plate 4 is also automatically guaranteed.

FIG. 5 is a perspective view of the process cartridge as seen from below. In the figure, 12b is a gear for receiving a drive from the main body, and is fixed to the end of the photosensitive drum 12 integrally with the drum.

FIG. 6 shows a drive mechanism for the drum 12. The drive gear C provided in the lower housing A meshes with the gear 12b as shown in the drawing, so that the drive from the lower housing is performed by the drum 12. Be transmitted to.

Next, the image forming apparatus shown in FIG. 7 has a reflection mirror 14a in the upper housing in addition to the scanner in the lower housing A as optical means.

The reflection mirror 14a is fixed to the mirror holder 14c, and as shown in FIG.
Both ends of 4c are hooks 14 at the opening of the side wall of the opening / closing cover.
It is held by being engaged with d and is urged downward from above by a pressing leaf spring 14b fixed to the upper casing.

On the main body side, 14e is a mirror pedestal in which the lower surfaces of both ends of the mirror holder 14c are abutted against the slopes and positioned as shown in FIG. Reference numeral 14f denotes a scanner pedestal on which the laser scanner 14 is mounted and positioned, and is integrally molded together with the drum bearing pedestal 18b and the mirror pedestal from a reinforced plastic made of glass-filled polycarbonate or the like to ensure mutual dimensional accuracy and mechanical strength. It is a frame structure. FIG. 9 shows a perspective view of the device when the upper housing is opened.

With the above construction, when the opening / closing cover 8 is in the closed state, the laser scanner 14 as a light source, the registration roller pair 3 required for sheet conveyance, the photosensitive drum 12, and the reflection mirror 1 are provided.
Not only can the 4a be positioned integrally with the lower housing with high dimensional accuracy, but vibration can be extremely reduced by sufficiently increasing the mechanical strength of the integrated frame.

In FIG. 7, arrow C indicates the loading direction of the process cartridge. FIG. 8 is a sectional view of the apparatus in a state in which the upper casing is closed and an image is formed,
FIG. 11 shows a partial side view of the 0-reflecting mirror 14a immediately before being positioned by the mirror pedestal 14e.

The present invention is an image forming apparatus using a process cartridge in which two or more image forming means such as a developing device, a cleaning device, and a charging device are integrally supported by a supporting device, such as a computer, a facsimile, a personal computer, It can be applied to an image forming apparatus such as a copying machine or a word processor for outputting images such as characters and drawings on a recording material.

As described above, by fitting the positioning member provided in the lower housing with the rotation center axis of the photosensitive member, it is possible to perform accurate positioning with the main part of the optical system that requires positional accuracy with the process cartridge. became. Further, the positioning of the transfer guide plate, the transfer charger and the like can be automatically performed at the same time, but they may be provided if necessary. Also, since the main part of the optical system is not provided in the upper housing, the structure for supporting the rotation of the housing may be simple, and it is possible to provide an image forming apparatus that is light and easy to operate for the user. It was

Even in the apparatus having the reflection mirror shown in FIG. 7, when the opening / closing cover is simplified as much as possible and the process cartridge and the reflection mirror incorporated in the opening / closing cover are closed without increasing the dimensional accuracy, Correctly positioned on the lower housing side. Further, since the laser scanner and the reflection mirror as the light source, the registration roller pair, and the image forming means such as the photosensitive drum of the process cartridge are substantially integrally coupled on the lower housing side, the positioning can be performed with high accuracy. There is an effect that the image quality can be maintained extremely good.

[0026]

As described in detail above, the present invention can provide an image forming apparatus capable of efficiently positioning the process cartridge with respect to the apparatus main body.

[Brief description of drawings]

FIG. 1 is a sectional view of an apparatus showing an embodiment of the present invention.

2 is a cross-sectional view of the device shown in FIG. 1 in a state in which an opening / closing cover is opened.

FIG. 3 is a partial side view of positioning means.

FIG. 4 is a plan view of the positioning unit shown in FIG.

FIG. 5 is a perspective view of the process cartridge as seen from below.

FIG. 6 is a perspective view of a drive mechanism.

FIG. 7 is a cross-sectional view of an apparatus having a reflection mirror.

FIG. 8 is a cross-sectional view of an apparatus having a reflection mirror.

9 is a perspective view of the apparatus shown in FIG. 7 when the upper housing is opened.

FIG. 10 is a partial side view showing a positioning state of a reflection mirror.

FIG. 11 is a partial side view showing a positioning state of a reflection mirror.

[Explanation of reference numerals] A lower casing B upper casing 9 process cartridge 9a process cartridge guide 12 photosensitive drum 12a rotation center axis 14a reflection mirror 14e mirror cradle 18a, 18b positioning block

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinwa Adachi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yasuyoshi Hayakawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Takeshi Setoriyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (2)

[Claims] 1. An image forming apparatus capable of mounting a process cartridge, wherein an upper housing is arranged to be openable and closable with respect to a lower housing, and the process cartridge is mounted on the upper housing and is used with the upper housing closed. The process cartridge can be mounted on the lower housing by the rotation center axis of the means for supporting the photosensitive member of the process cartridge and the central bearing member provided on the lower housing. apparatus. 2. An upper housing is arranged to be openable and closable with respect to a lower housing, and a process cartridge is loaded in the upper housing,
In an image forming apparatus in which a process cartridge can be mounted and which is used with the upper casing closed, a main part of an optical unit is provided in a lower casing, and a process cartridge and a part of the optical unit are provided in an upper casing. The positioning of the cartridge with respect to the lower housing is performed by the rotation center axis of the means for supporting the photosensitive member of the process cartridge and the central bearing member provided in the lower housing, while the lower housing of a part of the optical means of the upper housing is positioned. An image forming apparatus to which a process cartridge can be attached, characterized in that the positioning with respect to the body is performed by abutting an optical member that is not fixed to the upper casing with a locking member provided in the lower casing.