JPH11167333A - Electrophotographic image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce operation in the case of attachment/detachment of a process cartridge and also to surely perform positioning by linking the guide member of the process cartridge with the open/close cover of an aperture part. SOLUTION: When the process cartridge B is attached to an image forming device A, the open/close cover 18 is opened. At this time, a guide member 50 turns to a lower side from a horizontal position centering a rotary shaft 50h through a driving belt 60b linked with the movement of the cover 18, and stands by. An operator holds the grip 26 of the cartridge B, and places first and second projections 24 and 25 being members to be guided for positioning provided on a side wall in the longitudinal direction of a cleaning frame body on the guide plate 50b of a guide part 50. The cartridge B slides down on the plate 50b by its gravity. When the operator successively pushes the cover 18 up, the member 50 turns to an upper side by the driving belt 60b, and the cartridge B is positioned on the image forming device A.

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 to which a process cartridge can be attached and detached.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus using an electrophotographic image forming process, an electrophotographic photosensitive member and a process means acting on the electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is used as an electrophotographic image forming device. A process cartridge system that can be attached to and detached from the forming apparatus main body is employed. According to this process cartridge system, the maintenance of the apparatus can be performed by the operator himself without relying on a service person, so that the operability can be remarkably improved. Therefore, the process cartridge system is widely used in electrophotographic image forming apparatuses.

Conventionally, as shown in FIG. 9, a process cartridge B is provided with a first projection 24 for positioning and a second projection 24 for holding a posture on both side surfaces of the cleaning frame 14 in the longitudinal direction.
And the projection 25 are provided. The first projection 24 is provided on a coaxial extension with the rotation axis of the photosensitive drum 7,
The projection 25 is provided behind the process cartridge B in the insertion direction (the direction of the arrow P1) when the process cartridge B is mounted on the image forming apparatus A. Further, a handle 26 is integrally provided on the upper surface of the cleaning frame 14. On the other hand, the image forming apparatus A
Is provided with an openable / closable cover 18 that can be opened and closed about the shaft 16. When the cover 18 is opened, a cartridge mounting space is provided inside the apparatus main body 17, and mounting guide members 20 as cartridge mounting means are mounted on both left and right sides of the space. The guide member 20 includes the first protrusion 2 of the process cartridge B.
Guide groove 20 for guiding fourth and second protrusions 25
a is provided obliquely downward, and a positioning concave portion 20b is provided at the lower end thereof so as to be bent downward.

Accordingly, the operator grips the handle 26 to hold the first cartridges provided at both longitudinal ends of the process cartridge B.
Is engaged with the groove 20a. Next, when the process cartridge B is further pushed in along the groove 20a, the second protrusions 25 provided on both ends in the longitudinal direction of the process cartridge B engage with the groove 20a. Next, the first projection 24 and the second projection 2 of the process cartridge B are formed.
5 is inserted along the groove 20a while being fitted into the guide groove 20a. Due to the action of the moment, the process cartridge B slightly rotates clockwise about the second projection 25, and the first projection 24 falls into the positioning recess 20b to perform positioning.
Is completed.

Next, a case where the process cartridge B is removed from the image forming apparatus A in order to replace the process cartridge B will be described. First, even if the process cartridge B is to be pulled out as it is, it cannot be pulled out because the first projection 24 is fitted into the positioning recess 20b. Therefore, it is necessary to pull out the first projection 24 and the positioning recess 20b after releasing the fitting state. When the operator pulls the handle 26 toward the user, the process cartridge B rotates counterclockwise with the second protrusion 25 as a fulcrum,
The fitted state between the and the recess 20b is easily released. When the handle 26 is further pulled in this state, the first projection 24 and the second projection 25 slide along the guide groove 20a, and the process cartridge B is pulled out.

[0006]

SUMMARY OF THE INVENTION The present invention is a further development of the prior art, which reduces the work required when an operator attaches and detaches a process cartridge to and from the image forming apparatus main body, and ensures that the process cartridge is securely mounted. It is an object of the present invention to provide an electrophotographic image forming apparatus that can be positioned in an image forming apparatus main body.

[0007]

According to a first aspect of the present invention, there is provided an electrophotographic image forming apparatus for detachably attaching a process cartridge to form an image on a recording medium, comprising: a space for mounting the process cartridge; A movable guide member disposed in a space for mounting the process cartridge and guiding a guided member of the process cartridge, and an opening / closing cover for opening and closing an opening to the outside of the space for mounting the process cartridge,
An electrophotographic image forming apparatus, wherein the guide member and the opening / closing cover are interlocked.

According to a second aspect of the present invention, the guide member is pivotally attached to an image forming apparatus main body at a depth side of a space where a process cartridge is mounted when viewed from the opening, and when the opening / closing cover is opened. The guide member pivots downward from the horizontal toward the opening of the image forming apparatus main body, and when the openable cover is closed, the guide member pivots upward from the horizontal toward the opening. An electrophotographic image forming apparatus according to the first aspect, characterized in that:

According to a third aspect of the present invention, the guide member has a locking portion for positioning a process cartridge by locking guide members provided at both longitudinal ends of the process cartridge. Alternatively, an electrophotographic image forming apparatus according to the second aspect is provided.

According to a fourth aspect of the present invention, the center of rotation of the guide member is offset from the center of the guided member of the process cartridge. Is an electrophotographic image forming apparatus.

According to a fifth aspect of the present invention, the guide member is rotated at least 20 ° below horizontal and at least 20 ° above horizontal. An electrophotographic image forming apparatus according to one of the above aspects.

In a sixth aspect of the present invention, when the process cartridge is mounted on the main body of the image forming apparatus, the opening / closing cover contacts the process cartridge and applies a force for positioning the process cartridge relative to the main body of the image forming apparatus. A first to a fifth feature having an elastic member.
An electrophotographic image forming apparatus according to any one of the above aspects.

According to a seventh aspect of the present invention, a drive shaft coupling is provided on a coaxial core with a rotation input portion of the process cartridge in a state where the process cartridge is mounted, the drive shaft coupling being engaged with and disengaged from the rotation input portion. The electrophotographic image forming apparatus according to any one of the first to sixth inventions, wherein the positioning member for the guided member of the non-driving side process cartridge on the opposite side is fixed.

According to an eighth aspect of the present invention, in the seventh aspect, the drive shaft coupling portion rotates about an immovable center of rotation, and the rotation input portion is automatically aligned with the rotation input portion of the process cartridge. An electrophotographic image forming apparatus according to the present invention.

According to a ninth aspect of the present invention, there is provided a drive which is coaxial with an electrophotographic photosensitive drum provided in a process cartridge and is connected to a drive source which is detachably connected to a drum gear fixed to the electrophotographic photosensitive drum by a detaching operation of the process cartridge. The electrophotographic image forming apparatus according to any one of the first to sixth inventions, further comprising a gear, wherein a positioning member for the guided member is fixed.

According to a tenth aspect of the present invention, the guided member has a cylindrical portion, and the positioning member is connected to a bus bar at a position substantially perpendicular to the cylindrical portion of the guided member. An electrophotographic image forming apparatus according to any one of claims.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a process cartridge and an electrophotographic image forming apparatus according to the present invention will be specifically described with reference to the drawings. In the following description, the longitudinal direction refers to a direction perpendicular to and horizontal to the direction in which the process cartridge is inserted into the apparatus main body. The direction orthogonal to the longitudinal direction is referred to as the lateral direction.

(Embodiment 1) The embodiment 1 will be described with reference to FIGS. FIG. 1 is an explanatory diagram of a configuration of an image forming apparatus in a state where a process cartridge is mounted. FIG. 2 is a main sectional view of the process cartridge. FIG. 3 is an explanatory diagram of a configuration of a guide member of the process cartridge. FIGS. 4, 5, and 6 are explanatory views of the detached state of the process cartridge. FIG. 7 is a view for explaining a driving method of the guide member (a view from the lower side of the image forming apparatus), and FIG. 8 is a side view for explaining positioning on the side opposite to the driving side. [Overall Configuration] As shown in FIG. 1, the image forming apparatus A forms an image on the recording medium 2 by an electrophotographic image forming process. Then, a toner image is formed on a drum-shaped electrophotographic photosensitive member 7 (hereinafter, referred to as a photosensitive drum) as an image carrier. And, in synchronization with the formation of the toner image,
The recording medium 2 set on the feed tray 3a is transported by a transport unit 3 including a pickup roller 3b and a paper feed roller 3c. Next, the toner image formed on the photosensitive drum 7 of the process cartridge B is transferred to the recording medium 2 by applying a voltage to a transfer roller 4 that is pressed against the photosensitive drum 7 and rolls as a transfer unit. Thereafter, the recording medium 2 to which the toner image has been transferred is guided by the guide plate 3d, and is conveyed to the fixing unit 5. This fixing means 5
A fixing rotator 5b containing a heater, and the rotator 5b
The recording medium 2 is fixed to the recording medium 2 by applying heat and pressure to the recording medium 2 by applying pressure and heat to the recording medium 2. The recording medium 2 is conveyed by a discharge roller pair 3f (see FIG. 4) and discharged to a discharge unit 6.

[Process Cartridge] On the other hand, as shown in FIG. 2, the process cartridge B rotates a photosensitive drum 7 having a photosensitive layer as an image carrier, and the surface thereof is charged by a charging roller 8 serving as charging means. It is uniformly charged by voltage application. Next, a laser beam light corresponding to image information is irradiated from the optical system 1 to the photosensitive drum 7 through the exposure opening 9 to form an electrostatic latent image, and is developed by the developing unit 10 using toner. That is, the charging roller 8 is provided in contact with the photosensitive drum 7,
Is charged. The developing means 10 includes the photosensitive drum 7
To supply the toner to the developing area, and develop the latent image formed on the photosensitive drum 7.

The developing means 10 supplies the toner in the toner chamber 10a to the developing chamber 10b, rotates the developing roller 10c attached to the developing chamber 10b, and removes the toner layer provided with the triboelectric charge by the developing blade 10d. It is formed on the surface of a developing roller 10c having a fixed magnet built therein, and supplies the toner to the developing area of the photosensitive drum 7. Then, the toner is transferred to the photosensitive drum 7 in accordance with the latent image, thereby forming a toner image and visualizing the toner image.

Then, a voltage having a polarity opposite to that of the toner image is applied to the transfer roller 4 to transfer the toner image formed on the photosensitive drum 7 to the recording medium 2.
1, the residual toner on the photosensitive drum 7 is removed.
Here, the cleaning means 11 scrapes off the toner remaining on the photosensitive drum 7 by the elastic cleaning blade 11a and collects it in the waste toner reservoir 11b.

Each component such as the photosensitive drum 7 is housed in a cartridge frame formed by connecting a toner developing frame 12, a toner developing wall member 13, and a cleaning frame 14, to form a cartridge. . That is, the toner developing frame 12 and the toner developing wall member 13 are welded to each other to form the toner chamber 1.
0a and a developing chamber 10b, and a developing roller 10c and a developing blade 10d are attached to the developing chamber 10b. The cleaning frame 14 is provided with the photosensitive drum 7, the charging roller 8, and members constituting the cleaning unit 11. Then, the process cartridge B is configured by swingably coupling the toner developing frame 12 and the cleaning frame 14.

(Configuration of Guide Member) Next, the configuration of the guide member will be described with reference to FIGS.

In the image forming apparatus A, as shown in FIG. 1, an opening / closing cover 18 has a shaft 19a with respect to the apparatus main body 17 (see FIG. 7).
It is mounted so that it can rotate around the center. When the opening / closing cover 18 is opened, a guide member 50 for guiding the process cartridge B is provided inside the apparatus main body 17. The guide member 50 is swingably attached to the apparatus main body 17 by a rotation shaft 50h. The root gear portion 50f of the guide member 50 is provided with the rotation shaft 50h as a center, and linearly guides the guide plate 50b,
The attitude holding portion 50e is provided in parallel, the lower guide plate 50b is longer than the upper attitude holding portion 50e, and the upper end of the guide plate 50b is open, and the process cartridge B is placed on the lower 50b. Can be brought in from above and placed. The guide member 50 is provided on the opening and closing cover 1.
It rotates in accordance with the opening and closing of 8.

As shown in FIG. 7, the guide member 50 is driven by providing a gear 19 coaxially with a shaft 19a which is the center of rotation of the cover 18, and coaxially with a guide drive gear 60a1 meshing with the gear 19. A certain pulley 60a;
The driving force of the opening / closing cover 18 is transmitted to the guide member 50 by a belt 60b that is applied to a pulley 60c that is coaxial with a guide driving gear 60c1 that meshes with a gear portion 50f on the outer periphery of the guide member 50. In the present embodiment, the belt 60b is used as the drive transmission means 60.
A gear or the like may be used.

The structure of the guide member 50 will be described in more detail with reference to FIGS. 3, 4, 5, 6, and 8. FIG.
FIG. 3 is a detailed explanatory view of the guide member, FIGS. 4, 5, and 6 are diagrams for explaining the movement of the opening / closing cover 18 and the guide member 50 and the detached state of the process cartridge B. FIG. FIG. 4 is a view for explaining a positioning part of FIG.

When the operator mounts the process cartridge B on the image forming apparatus A (see FIG. 4), the operator opens the opening / closing cover 18. At this time, as described above, in conjunction with the movement of the opening / closing cover 18,
The guide member 50 pivots about the rotation shaft 50h below the horizontal position and stands by. At this time, the rotation angle θ1 of the guide member 50 with respect to the horizontal line is an angle at which the process cartridge B is slid down the guide member 50 by its own weight when the process cartridge B is taken out from the image forming apparatus A, which will be described later. is there. This angle θ
1 is experimentally found to be preferably 20 ° or more.

The operator holds the handle 2 of the process cartridge B.
6, a first projection 24 serving as a guided member for positioning and a second projection 25 for holding a posture provided on the longitudinal end wall of the cleaning frame 14 of the process cartridge B. 50 on the guide plate 50b.
The first projection 24 is provided on an extension of the same axis as the rotation axis of the photosensitive drum 7, and the second projection 25 is more capable of mounting the process cartridge B than the first projection 24 on the image forming apparatus A.
It is provided on the rear side with respect to the direction in which it is mounted. Also,
When the process cartridge B is placed on the guide plate 50b, the guide plate 50b slides down due to the weight of the process cartridge B. Therefore, the guide member 50 has a stopper 50a for locking the second protrusion 25. It is arranged. By having the stopper portion 50a,
Even if the guide member 50 is inclined downward, the process cartridge B does not fall into the image forming apparatus A.

Subsequently, as shown in FIG. 5, when the operator pushes up the opening / closing bar 18 (in the direction of arrow C), the drive transmitting means 60 also pushes up the guide member 50 in the direction of arrow D and turns upward. When the rotation angle of the guide member 50 exceeds the horizontal level, the first protrusion 24 and the second protrusion 25 of the process cartridge B move along the guide plate 50b of the guide member 50 to reduce its own weight. As a result, it starts moving in the direction of arrow E.

Further, when the operator pushes up the opening / closing cover 18 and closes the opening / closing cover 18 (see FIG. 6), the guide member 50 rotates upward and reaches the rotation angle θ2 from the horizontal direction to the upward direction. Then, the process cartridge B
Due to its own weight, the outer periphery of the first projection 24 in the insertion direction abuts on the locking portion 50c of the guide member 50. The locking portion 50c is connected to the rotation shaft 50 of the guide member 50.
h, it is disposed rearward as viewed from the mounting direction of the process cartridge B. That is, the first projection 24 is
The rotation shaft 50h is offset from the center of the first projection (cylindrical) 24 in a state where the rotation axis 50h abuts on 0c. The locking portion 50c has the same arc shape as the first projection 24. Further, when the opening / closing cover 18 is closed, the handle 26 is urged by the elastic member 61 disposed on the opening / closing cover 18 so that the first
Of the projection 24 is surely pressed by the locking portion 50c. Further, the presence or absence of a drum drive coupling (shaft coupling) 70 (see FIG. 7) coaxial with the locking portion 50c and the center 50g of the first projection 24 detects the presence or absence of a process cartridge B (not shown). In conjunction with the detecting means, a drum coupling (a shaft coupling, which is fitted to the rotation input portion 71 of the process cartridge B and is driven) is provided at the end of a drum shaft 7a fixed to the center of the photosensitive drum 7 of the process cartridge B. Is automatically aligned when is transmitted.
When the drive is transmitted to the process cartridge B, a rotational force is applied in the direction of arrow F (see FIG. 3), which is the drive direction, so that the second protrusion 25 is held by the attitude holding portion 50e of the guide member 50, Process cartridge B
Is positioned in the image forming apparatus A.

As shown in FIG. 8, the first projection 24 on the non-drive side of the process cartridge B is positioned by engaging a positioning portion 80 provided on the image forming apparatus main body 17. The positioning portion 80 is a member different from the guide member 50 and is fixed to the apparatus main body 17. The positioning portion 80 has positioning surfaces 80a and 80b substantially perpendicular to each other so as to be in contact with the generatrix at a position substantially perpendicular to the first projection 24, which is a cylindrical guided member. The substantially vertical surface 80a determines the mounting direction of the process cartridge B, and the substantially horizontal surface 80b mainly supports the weight of the process cartridge B. The locking portion 50j of the guide member 50 that guides the first protrusion 24 on the non-drive side is formed to be larger than the curvature of the first protrusion 24.

A gear (referred to as a drum gear) is provided at the end of the photosensitive drum 7 coaxially with the photosensitive drum 7, and when the process cartridge B is mounted on the apparatus main body 17, the drum gear is provided on the apparatus main body 17. When the driving force is transmitted from the apparatus main body 17 to the process cartridge B by meshing with the drive gear connected to the source, the positioning portion 80 is brought into contact with the first projections 24 on both sides in the longitudinal direction of the process cartridge B. So that it is provided on both sides of the cartridge mounting portion. In addition, the first projection 2
The reference numeral 4 may be, for example, a partially circular cross-section, as long as it satisfies that the guide member 50 is guided by the guide member 50 and that there is an arc bus bar abutting the positioning portion 80 and an arc contacting the locking portion 50c.

Next, when the process cartridge B is taken out of the image forming apparatus A, when the cover 18 is opened, a sensor (not shown) disposed on the cover 18 is used.
From the drum drive coupling 70
Is disengaged from the drum coupling 71, and furthermore, the guide member 50 is rotated downward, whereby the process cartridge B slides down by its own weight along the guide plate 50b, and the second projection 25 is Stopper part 5
0a, and retracts to the take-out position. In this embodiment, a coupling unit is used as a driving unit of the photosensitive drum, but the present invention is not limited to the coupling unit. Further, the guide plate 50b of the guide member 50 is linear, but it is also possible to form the guide plate 50b into a curved shape in consideration of the movement of mounting and removing the process cartridge B.

[0034]

As described above, according to the present invention, the operator can place the process cartridge on the guide member of the image forming apparatus main body and open / close the opening / closing door to automatically attach / detach the process cartridge. Thus, the work of the operator can be reduced. Further, it is possible to provide an electrophotographic image forming apparatus which can eliminate the mounting failure of the process cartridge due to the unfamiliar operation of the operator and can surely position the process cartridge in the image forming apparatus main body.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electrophotographic image forming apparatus in a state where a process cartridge is mounted.

FIG. 2 is a vertical sectional view of a process cartridge.

FIG. 3 is a side view for explaining a detailed configuration of a guide member.

FIG. 4 is a longitudinal sectional view showing a detached state of a process cartridge.

FIG. 5 is a longitudinal sectional view showing a detached state of the process cartridge.

FIG. 6 is a longitudinal sectional view showing a detached state of the process cartridge.

FIG. 7 is a plan view for explaining a driving method of a guide member.

FIG. 8 is a side view for explaining a method of positioning the process cartridge on the non-driving side.

FIG. 9 is a longitudinal sectional view illustrating a configuration of a conventional image forming apparatus in a state where a process cartridge is mounted.

[Explanation of symbols]

A: Image forming apparatus B: Process cartridge 1: Optical system 2: Recording medium 3: Transport means 3a: Feed tray 3b: Pickup roller 3c: Feed roller 3d: Guide plate 3f: Discharge roller 4: Transfer roller 5: Fixing Means 5a: pressure roller 5b: fixing rotator 7: photosensitive drum 7a: drum shaft 8: charging roller 9: exposure opening 10: developing means 10a: toner chamber 10b: developing chamber
10c developing roller 10d developing blade 11 cleaning means 11a cleaning blade 11b waste toner reservoir 12 toner developing frame 13 toner developing wall member 14 cleaning frame 16 shaft 17 device body 18 opening / closing cover 19 ... Gear 19a ... Shaft 20 ... Installation guide member 20a ... Guide groove 20b ... Positioning recess 24 ... First protrusion 25 ... Second protrusion 26 ... Handle 50 ... Guide member 50a ... Stopper part 50b ... Guide plate 50c ... Locking part 50e ... posture holding unit 50f
... Gear part 50g ... Center 50h ... Rotary shaft 50j ... Locking part 60 ... Drive transmission means 60a ... Pulley 60a1 ... Drive gear 60b ... Belt 60c ... Pulley 60c1
... Driving gear 61 ... Elastic member 70 ... Drum drive coupling 71 ... Drum coupling 80 ... Positioning part 80a, 80b ... Positioning surface

Claims (10)

[Claims] 1. An electrophotographic image forming apparatus for detachably attaching a process cartridge to form an image on a recording medium, comprising: a space for mounting the process cartridge; and a process cartridge disposed in the space for mounting the process cartridge. A movable guide member that guides the guided member; and an open / close cover that opens and closes an opening to the outside of a space where the process cartridge is mounted. The guide member and the open / close cover are interlocked. Electrophotographic image forming apparatus. 2. The image forming apparatus according to claim 1, wherein the guide member is pivotally attached to a main body of the image forming apparatus at a rear side of a space where the process cartridge is mounted when viewed from the opening. 2. The device according to claim 1, wherein the guide member pivots downward from the horizontal toward the opening of the apparatus body, and the guide member pivots upward from the horizontal toward the opening when the open / close cover is closed. 2. The electrophotographic image forming apparatus according to 1. 3. The electronic device according to claim 1, wherein the guide member has a locking portion that locks guided members disposed at both ends in the longitudinal direction of the process cartridge to position the process cartridge. Photographic image forming device. 4. The electrophotographic image forming apparatus according to claim 2, wherein a center of rotation of the guide member is offset with respect to a center of a guided member of the process cartridge. 5. The guide member is 20 ° below horizontal.
The electrophotographic image forming apparatus according to any one of claims 2 to 4, wherein the electrophotographic image forming apparatus is rotated upward by 20 degrees or more from horizontal. 6. The opening / closing cover has an elastic member which, when the process cartridge is mounted on the image forming apparatus main body, applies a force for positioning the process cartridge with respect to the image forming apparatus main body by contacting the process cartridge. The electrophotographic image forming apparatus according to any one of claims 1 to 5, wherein 7. When the process cartridge is mounted, a drive shaft coupling is provided on the same axis as the rotation input portion of the process cartridge so as to be engaged with and disengaged from the rotation input portion. 7. The electrophotographic image forming apparatus according to claim 1, wherein a positioning member for a guided member of the process cartridge on the side is fixedly provided. 8. The electrophotographic image forming apparatus according to claim 7, wherein the drive shaft coupling portion rotates about an immovable rotation center, and the rotation input portion is automatically aligned in a state where the rotation input portion is engaged with the rotation input portion of the process cartridge. apparatus. 9. A guided gear having a drum gear fixed to the electrophotographic photosensitive drum coaxially with the electrophotographic photosensitive drum provided in the process cartridge and a drive gear connected to a drive source engaged and disengaged by the mounting and dismounting operation of the process cartridge. 7. The electrophotographic image forming apparatus according to claim 1, wherein a positioning member for the member is fixed. 10. The guided member has a cylindrical portion,
The electrophotographic image forming apparatus according to any one of claims 7 to 9, wherein the positioning member contacts a generatrix at a position substantially perpendicular to a cylindrical portion of the guided member.