JPH10105018A - Image forming device and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device capable of making attaching/ detaching operations easy and sure, when it is constituted so that the attaching/ detaching directions of a process cartridge are in the axial direction of the process cartridge, with respect to an image forming device main body and the process cartridge used for the image forming device. SOLUTION: An arm 20 for supporting a shutter 18 is rocked through a shutter driving gear 24, an idler gear 25 and a shutter gear 26 by the turning operation of a locking means 22 for fixing a developing unit in the axial direction, with respect to a device main body, to open/close the shutter 18. When a stopper means 23 restrains/holds the shutter 18 at a position where it is opened, to remove the developing unit from the device main body, the shutter 18 is released from the stopper means 23, to be closed.

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 or a printer, and a process cartridge used for the same.

[0002]

2. Description of the Related Art An example of an electrophotographic image forming apparatus for forming an image on a transfer material by using an electrophotographic image forming method includes:
For example, electrophotographic copying machines, electrophotographic printers (eg, laser beam printers, LED printers, etc.), facsimile machines, word processors, and the like have been put to practical use.

A process cartridge detachably mountable to the main body of the image forming apparatus has a cartridge in which at least two or more elements including a charging means, a developing means, a cleaning means, an electrophotographic photosensitive member and the like are integrally formed. When a component such as a developer is replenished or a component whose life has expired is replaced, the process cartridge can be replaced with a new one for each process cartridge, which facilitates maintenance and improves reliability.

Here, the configuration of a conventional color laser printer will be described with reference to FIGS. In FIG. 12, a rotary developing device 10 is provided inside an image forming apparatus main body 101.
2. An image carrier 104 including an intermediate transfer body 103 and an electrophotographic photosensitive drum is provided.

[0005] The transfer material P fed from a cassette 105 disposed below the main body 101 of the image forming apparatus is wound around the intermediate transfer member 103 and conveyed, and the toner image formed on the surface of the image carrier 104 is removed. Fixing device transferred to transfer material P
The toner is permanently fixed by 106 and discharged outside the machine.

The rotary developing device 102 includes magenta, cyan,
It has four color developing units 102M, 102C, 102Y and 102B provided with four color toners of yellow and black. These four color developing units 102M, 102C, 102Y, 102B are arranged rotatably with respect to the shaft 102a. A revolving gear is provided on the shaft 102a, and each of the developing devices 102M, 102C, 102Y, and 102B rotates in conjunction with a revolving gear disposed on the outer periphery of the revolving gear. , 102C, 102Y, and 102B are kept constant.

At the time of image formation, developing units 102M, 102C,
Of the 102Y and 102B, the developing device of the color corresponding to the latent image is stopped at a position facing the image carrier 104, and the developing roller is further there.
102b is positioned so as to face the surface of the image carrier 104 with a small space therebetween. During development, the developing roller
The latent image on the image carrier 104 is developed by the application of the bias and the rotational drive of the bias 102b to form a toner image.

A supply roller 102d is in sliding contact with a developing roller 102b disposed in each of the developing units 102M, 102C, 102Y, and 102B. An agent (toner) is supplied.

The developing devices 102M, 102C, 102Y, and 102B are configured as a process cartridge in which a developer container, a developing roller 102b, a supply roller 102d, and the like are integrally formed as a cartridge. It is configured to be possible.

The developing devices 102M, 102C, 102Y and 102B as such process cartridges are
Developing devices 102M, 102C, 102Y, which are process cartridges
Although the developing roller 102b is used with the developing roller 102b exposed from the developing cartridge 102B, the process cartridge does not damage the rotating developing device 102 so that the developing roller 102b is not damaged before the process cartridge is mounted on the rotating developing device 102. Until it is completely installed, the exposed developing roller 10
In general, a configuration is adopted in which 2b is protected by covering it with a shutter or the like.

As for the shutter opening / closing means, for example, as shown in FIGS. 13 and 14, the opening / closing operation of the shutter 203 is controlled by the image forming apparatus main body 20 of the process cartridge 202.
In general, it is linked with the attachment / detachment operation for 1.

As shown in FIG. 13 and FIG. 14, the process cartridge 202 is in the transverse direction of the process cartridge 202 with respect to the image forming apparatus main body 201 (the direction perpendicular to the axis of the built-in rotating body). In the direction of arrow A. The process cartridge 202 is provided with an openable and closable shutter 203 which is constantly urged in the direction of the closed position by the urging means, as shown in FIG. 14, when the process cartridge 202 is inserted into the image forming apparatus main body 201. A cam 204 provided on the shutter 203 is engaged with a part of the main body 201 of the image forming apparatus to move and open the shutter 203 against the urging force of the urging means.

[0013]

[Problems to be solved by the invention] However, FIG.
In the conventional technique shown in FIG.
Since the direction of attachment and detachment of the image forming apparatus main body 201 with respect to the image forming apparatus main body 201 is up and down with respect to the image forming apparatus main body 201, if the size of the image forming apparatus main body 201 is increased due to high speed, network compatibility, and diversification of paper handling, the There is a problem that operability when attaching and detaching the cartridge 202 is deteriorated.

That is, it is desirable that the replacement of the consumable parts such as the process cartridge and the transfer material can be performed from one direction of the image forming apparatus main body. In the color laser printer shown in FIG. It is desirable that the direction is the longitudinal direction (the axial direction of the built-in rotating body) with respect to the image forming apparatus main body 101.

However, if the insertion direction of the process cartridge is set to the longitudinal direction, there is a problem that the configuration of the insertion portion of the process cartridge and the shutter becomes complicated, and the operation of the user becomes complicated.

The present invention solves the above problems,
An object of the present invention is to provide an image forming apparatus which can easily and reliably mount and remove the process cartridge when the mounting direction of the process cartridge is set in the axial direction of the process cartridge with respect to the image forming apparatus main body, and a process cartridge used in the image forming apparatus. Is to be provided.

[0017]

A typical configuration according to the present invention for achieving the above object is an electrophotographic photosensitive member, a charging unit for charging a surface of the electrophotographic photosensitive member,
Cleaning means for removing residues on the surface of the electrophotographic photoreceptor, a cleaning container for containing the residues, the electrophotographic photoreceptor and the charging means,
A developing rotator for supplying a developer to the electrophotographic photosensitive member for developing a latent image formed on the electrophotographic photosensitive member, and a supply rotating member for supplying a developer to the surface of the developing rotator And a developing blade for applying a thin layer of the developer on the surface of the developing rotator, and for applying a charge to the developer, and at least two or more of a developer container for containing the developer. A process cartridge having an openable and closable shutter which is always urged toward a closed position by an urging means to protect a part where the element is exposed while protecting the element is axially moved with respect to the image forming apparatus main body. In a detachable image forming apparatus, a mounting operation of the process cartridge to the image forming apparatus main body and an opening / closing operation of the shutter can be performed independently. The image forming apparatus according to.

According to the above configuration, the mounting operation of the process cartridge to the image forming apparatus main body and the opening and closing operation of the shutter are performed independently and separately. Therefore, the configuration is simplified, and each operation is ensured. Erroneous operation can be prevented.

The image forming apparatus further comprises a lock means for preventing the process cartridge from being detached in the mounting direction after the process cartridge is mounted on the image forming apparatus main body. The lock means is provided on the process cartridge by an operation when the lock means operates. The shutter is configured to swing from a closed position to an open position.

With the above arrangement, after the process cartridge is mounted on the image forming apparatus main body, the locking means is operated to prevent the process cartridge from being removed in the mounting direction, and the shutter is moved from the closed position to the open position. Due to the swing, the operability is good and the trouble of the user's operation can be reduced.

Further, there is provided stopper means for holding the shutter at an open position independently of the lock means,
When the shutter swings to the open position by the operation of the lock means, the shutter engages with the stopper means to hold the shutter at the open position against the urging force of the urging means, and It is characterized in that the urging force of the urging means is not applied to the lock means.

As described above, the operation of swinging the shutter of the process cartridge from the closed position to the open position is performed by the lock means. However, if the urging force of the urging means of the shutter is still applied to the lock means, some operation is performed. If the locking means is released by an impact or the like, the process cartridge may be detached from the image forming apparatus main body or the shutter may swing from the open position to the closed position. Since the stopper unit receives the urging force of the urging unit to be urged and does not act on the locking unit, the load on the locking unit is eliminated, and the process cartridge is removed in the mounting direction after the process cartridge is mounted on the image forming apparatus main body. The locking can be reliably performed by the locking means.

Further, the stopper means is configured not to interfere when the process cartridge is detached from the image forming apparatus main body, and the stopper means is provided when the process cartridge is detached from the image forming apparatus main body. When the engagement with the shutter is released, the shutter swings to the closed position by the urging force of the urging means.

As described above, since the locking means of the process cartridge and the stopper means of the shutter are independent and separate, even if the locking means is released, the shutter remains held at the open position by the stopper means. Become. Therefore, with the above configuration, the process cartridge can be detached from the image forming apparatus main body without any trouble even when the stopper means acts on the shutter and opens the shutter, and in the detaching operation, the shutter of the stopper means is removed. And the shutter automatically swings to the closed position by the urging force of the urging means, thereby minimizing the user's operation and improving the operability.

According to another aspect of the present invention, in the process cartridge detachably mounted to the image forming apparatus, the swing operation of the shutter from the closed position to the open position is performed by a speed-up movement by a gear train. A process cartridge configured to operate.

According to the above configuration, the shutter can be smoothly moved from the closed position to the open position by the gear-driven speed-up movement, and the operation of the user can be minimized. By driving, the shutter can be opened and closed reliably in a small space.

Further, the gear train is provided with a mark for assembling the gear train in phase.

As described above, when the opening and closing operation of the shutter is performed by the speed-up movement by the gear drive, the shift of one tooth of the gear greatly affects the momentum of the shutter. Therefore, it is necessary to accurately assemble the phase of the gear train during assembly,
With the above configuration, by assembling the gear train with the mark provided on the gear train as a guide, the phase of the gear train can be easily adjusted and assembled, and the swinging operation from the closed position of the shutter to the open position is reliably stabilized. You can do it.

[0029]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of an image forming apparatus according to the present invention and a process cartridge used in a color laser beam printer as an example. FIG. 1 is an explanatory cross-sectional view showing a configuration of an image forming apparatus according to the present invention, FIG. 2 is a perspective view showing a configuration of a process cartridge according to the present invention in which a shutter is omitted, and FIG. A perspective view showing a state of being attached to the main body,
FIG. 4 is a cross-sectional view showing an opening and closing operation of a shutter provided in the process cartridge. FIG. 5 is a perspective view showing a state in which the process cartridge is mounted on the image forming apparatus main body and locked by locking means. 7 is a perspective view showing the structure of the stopper means, FIG. 8 is a perspective view showing the positional relationship between the shutter, the lock means and the stopper means and the state of their interlocking operation, and FIG. 9 is an arm supporting the shutter and the stopper means. FIG. 10 is a cross-sectional explanatory view showing the interlocking operation of the shutter, the locking means and the stopper means, and FIG. 11 is a cross-sectional explanatory view showing the interlocking operation of the shutter and the stopper means.

First, the overall configuration of the image forming apparatus according to the present invention will be described with reference to FIG. In FIG. 1, the image forming apparatus conveys a transfer material P fed from a cassette 2 serving as a feeding unit to a registration roller 38 to be on standby, and forms an image formed of an electrophotographic photosensitive member rotating at a constant speed. A toner image formed of a developer formed on the surface of the image carrier 4 in an image forming unit including three color developing devices 8Y, 8M, and 8C rotatable indexably with respect to the image carrier 4 serving as a means is transferred to an intermediate transfer member. The color image developed by multiple transfer to 3 is
After being transferred onto the transfer material P conveyed synchronously by the registration rollers 38, the transfer material P is conveyed to the fixing device 5, and is discharged by the discharge rollers 6 to the discharge portion 7 on the upper portion of the image forming apparatus main body 1.

Further, a black developing device 8B fixed to the image forming apparatus main body 1 in the vicinity of the image carrier 4, and rotatable color developing devices 8Y and 8M of three colors (yellow, magenta and cyan) are provided. , 8C, the latent image formed on the image carrier 4 is developed in the image forming unit 8, and is multiply transferred onto the transfer material P to form a color image. You.

The rotatable color developing devices 8Y, 8M,
8C and the fixed black developing device 8B are separately detachable from the apparatus main body 1, and are color developing devices 8Y and 8 as an example of the process cartridge according to the present invention.
M and 8C are provided to the color developing units 8Y and 8
The sleeves 8YS, 8MS, and 8CS serving as developing rotators disposed inside the M and 8C and the supply rollers 8YR serving as supply rotators are provided.
It is configured to be removable in the axial direction (long direction) such as 8MR and 8CR.

The drum unit 9 is formed integrally with the image carrier 4 and a cleaning container 10 which also serves as a holder for the image carrier 4 and stores a residue on the surface of the image carrier 4. . The drum unit 9 is detachably supported with respect to the apparatus main body 1 so that the drum unit 9 can be easily replaced according to the life of the image carrier 4.

The image carrier 4 in this embodiment is formed by coating an organic photoelectric layer on the outside of a cylinder made of aluminum and having a diameter of about 62 mm, and is provided in a cleaning container 10 serving also as a holder for the image carrier 4. On the other hand, it is rotatably supported. In the vicinity of the outer periphery of the image carrier 4, the image carrier 4
A cleaner blade 11 serving as a cleaning unit for removing residues on the surface of the image carrier 4 and a primary charging unit 12 for charging the surface of the image carrier 4 are arranged.

The image carrier 4 rotates in the direction of arrow a in FIG. 1 in response to the image forming operation when the driving force of a drive motor (not shown) is transmitted to one end of the image carrier 4 on the far side in FIG.

The primary charging means 12 employs a contact charging method. The primary charging means 12, which is a conductive roller, is brought into contact with the image carrier 4 and a voltage is applied to the primary charging means 12 to apply an image. This is for uniformly charging the surface of the carrier 4.

Exposure to the image carrier 4 is performed from a scanner unit 13 arranged on the upper part of the apparatus main body 1. That is, when an image signal is given to a laser diode, the laser diode applies image light corresponding to the image signal to a polygon mirror.
Irradiate 14

The polygon mirror 14 is rotated at a high speed by a scanner motor, and the image light reflected by the polygon mirror 14 selectively passes through the imaging lens 15 and the reflection mirror 16 on the surface of the image carrier 4 which rotates at a constant speed. Exposure, and as a result, an electrostatic latent image is formed on the surface of the image carrier 4.

The image forming section 8 for visualizing the electrostatic latent image includes yellow, magenta, cyan,
Three color developing units 8 capable of developing each color of black
Y, 8M, 8C and one black developing device 8B.

The black developing device 8B is a fixed developing device.
At a position facing the image carrier 4, a sleeve 8BS serving as a developing rotator for supplying a black toner as a developer to the image carrier 4 is opposed to the image carrier 4 at a minute interval (300
μm), and forms a visible image with black toner corresponding to the electrostatic latent image on the image carrier 4.

On the other hand, three color developing units 8Y, 8M, 8
C includes toner corresponding to 6000 pages (A4 size, 5% printing), and is detachably supported by a developing rotary 8b that rotates about a shaft 8a.

At the time of image formation, each color developing unit 8
The Y, 8M, and 8C are rotated around the shaft 8a while being supported by the developing rotary 8b, and are moved to a predetermined color developing device 8A.
Y, 8M, 8C stop at the position facing the image carrier 4,
Sleeves 8YS, 8MS, and 8CS serving as developing rotators for supplying yellow, magenta, and cyan toners, which are developers, to the image bearing member 4 are provided with a small distance (30 mm) from the image bearing member 4.
(Approximately 0 μm), and a visible image is formed by color toner corresponding to the electrostatic latent image on the image carrier 4.

When a color image is formed, the developing rotary 8b rotates every one rotation of the intermediate transfer member 3, and the developing process is performed in the order of a yellow developing device 8Y, a magenta developing device 8M, a cyan developing device 8C, and then a black developing device 8B. Done.

FIG. 1 shows a state in which the yellow developing unit 8Y is positioned opposite to the image carrier 4 and is stationary.
The yellow developing device 8Y feeds the toner in a developer container for containing the developer to a supply roller 8YR that supplies the surface of the sleeve 8YS by a feed mechanism, and the supply roller 8YR and the sleeve that rotate clockwise in FIG. A thin layer of toner is applied to the surface of the sleeve 8YS rotating in the clockwise direction in FIG. 1 by a developing blade 8YB pressed against the outer periphery of 8YS, and a charge is applied to the toner (friction charging). Then, the sleeve 8 facing the image carrier 4 on which the latent image is formed
The toner is developed on the image carrier 4 in accordance with the latent image by applying a developing bias to YS.

The magenta developing device 8M and the cyan developing device 8C are also provided with the supply rollers 8MR and 8MR by the same mechanism as described above.
MR and sleeve 8MS, 8CS and developing blade 8MB, 8CB
Acts to perform the toner developing process.

The sleeves 8YS, 8MS, 8CS of the rotary developing devices 8Y, 8M, 8C are connected to the developing devices 8Y, 8M, 8C, respectively.
When C is rotationally driven to the developing position, it is connected to a high-voltage power supply for each color development and a driving means provided in the apparatus main body 1, and a voltage is sequentially and selectively applied for each color development to perform the rotational drive. .

Next, the constructions of the shutter mechanism, locking means, stopper means and the like of the developing devices 8Y, 8M, 8C which are constructed as an example of the process cartridge according to the present invention will be described in detail with reference to FIGS. . The yellow developing device 8Y, the magenta developing device 8M, and the cyan developing device 8C
Since both have the same shape, the configuration of the yellow developing unit 8Y will be described here.

FIG. 2 is a perspective view of the yellow developing unit 8Y without a shutter. As described above, if the developing device 8Y, which is a process cartridge, does not have a shutter for covering and protecting the key parts such as the sleeve 8YS, the key parts such as the sleeve 8YS are always exposed, and when the process cartridge is attached or detached. There is a risk that key parts such as the sleeve 8YS may be damaged during handling of the device.

Therefore, as shown in FIG.
By protecting the key parts such as the sleeve 8YS, the sleeve 8YS and the like are prevented from being damaged when the developing unit 8Y as a process cartridge is attached or detached or transported.

The shutter 18 has a fulcrum 19 shown in FIGS.
The developing device 8Y, which is a process cartridge, is swingable in directions indicated by arrows b and c in FIG. Torsion coil spring shown in FIG.
The shutter 18 is normally urged by the torsion coil spring 20a in the direction of the closed position (the direction of arrow c in FIG. 4).

When the shutter 18 is in the closed position (see the shutter 18) shown by the solid line in FIG. 4, the sleeve 8YS and the like in the developing unit 8Y are protected by opposing the sleeve 8YS and the like. Open position (shutter 18 '
), The sleeve 8YS or the like is exposed from the developing device 8Y so that a predetermined developing operation can be performed.

As shown in FIG. 3, an opening 8b2 corresponding to the outer shape of a developing device 8Y as a process cartridge is provided in a side plate 8b1 of a developing rotary 8b rotatably provided in the image forming apparatus main body 1. The developing unit 8Y is inserted into the opening 8b2 in the direction of arrow d in FIG. 3 in accordance with the shape of the opening 8b2, and is mounted on the apparatus main body 1 as shown in FIG.

At this time, since the opening 8b2 is formed in a shape corresponding to the outer shape of the developing device 8Y, the direction in which the developing device 8Y, which is a process cartridge, should be mounted to the apparatus main body 1 is determined. It is easy for the user to understand.

On the other hand, the developing rotary 8b provided on the apparatus main body 1 side is provided with a flange 21 shown in FIG.
A projection 8c provided at one end of the developing device 8Y on the flange 21
And the position of the developing device 8Y in the insertion direction is regulated and positioned.

At a position corresponding to the flange 21, a lock means 22 which is rotatable about a shaft 22a shown in FIG. 10 with respect to the developing rotary 8b is arranged. As shown, when the developing device 8Y is inserted into the opening 8b2, the locking means 22 is retracted to the position shown by the solid line in FIG. 5 (see the locking means 22), and the developing device 8Y is moved from the opening 8b2. With the projection 8c of the developing device 8Y having been inserted and abutting against the flange 21, the locking means 22 is
(See lock means 22 '), the projection 8c of the developing device 8Y is brought into contact with the flange 21 and the lock means.
22 and the developing device 8Y is rotated by the developing rotary 8b.
It is fixed in the axial direction (longitudinal direction) with respect to (the apparatus main body 1).

Further, on the side of the developing rotary 8b corresponding to the back side in the insertion direction of the developing device 8Y, the shutter 18 is held at the open position independently of the lock means 22, as shown in FIGS. Means 23 are provided rotatably about a shaft 23a with respect to the developing rotary 8b. The stopper means 23 includes a torsion coil spring 23e serving as urging means shown in FIG. 23e
11 is rotatable from the position shown by the solid line in FIG. 11 to the position shown by the broken line in a state where it is constantly urged in the direction of arrow g in FIG.

The boss 18 provided on the shutter 18
a is engaged with and locked by the stopper means 23, and the shutter
An open position 18 is indicated by a broken line in FIG. 11 (see shutter 18 ').
Is to be held.

Next, the operation of opening the shutter 18 of the developing device 8Y will be described in detail with reference to FIGS. As described above, in order to fix the developing device 8Y, the lock unit 22 is changed from the position shown by the broken line in FIG. 8 (see the lock unit 22) to the position shown by the solid line (the lock unit 22 ').
Reference).

A lock cam 22b is provided at the upper end of the lock means 22, as shown in FIG.
By rotating the shutter 22 in a direction indicated by an arrow e in FIG. 10, the shutter drive gear 24 comes into contact with a cam 24b provided on an adjacent shutter drive gear 24, and the shutter drive gear 24 is rotated about a shaft 24a in the direction indicated by an arrow f in FIG. To rotate.

A shutter gear 26 meshes with the shutter drive gear 24 via an idler gear 25, and an arm 20 supporting the shutter 18 is integrally attached to the shutter gear 26. Accordingly, the rotational force that causes the shutter drive gear 24 to rotate in the direction of arrow f in FIG. 10 is transmitted to the shutter gear 26 via the idler gear 25, and the shutter gear 26 moves in the direction of arrow b in FIG. By rotating, the shutter 18 swings to the position shown by the broken line in FIG. 10 (see the shutter 18 ') via the arm 20 fixed to the shutter gear 26, and is opened.

With the above configuration, the developing device 8Y, which is a process cartridge, is connected to the developing rotary 8b.
The shutter is rotated by operating the locking means 22 as a stopper in the mounting direction after mounting on the shutter.
18 can be opened.
The fixing of Y and the opening operation of the shutter 18 can be performed simultaneously, and the operability can be improved.

At this time, for the user, the mounting operation of the developing device 8Y, which is a process cartridge, and the locking means 22
The operation of opening the shutter 18 via the interface is an independent and independent operation, so that erroneous operations by the user can be prevented and each operation can be performed reliably. Further, since the mounting operation of the developing device 8Y to the developing rotary 8b and the opening and closing operation of the shutter 18 are performed independently and separately, the configuration of the apparatus can be simplified.

As described above, the opening and closing operation of the shutter 18 is performed by rotating the gear trains 24, 25 and 26 so that the arm 20 is rotated to open and close. The operation will be described in further detail. By rotating the lock means 22, the developing device 8Y is fixed. At this time, the locking means 22
Is an arrow e in FIG. 10 about the axis 22a as shown in FIG.
22 degrees in the direction. At this time, the shutter drive gear 24
When the cam 24b is pushed up by the lock cam 22b, the lock cam 22b rotates by 30 ° in the direction of arrow f in FIG. In response to this rotation, idler gear 25 moves clockwise in FIG.
Rotate 65 °. At this time, the gear ratio between the shutter drive gear 24 and the idler gear 25 has increased 5.5 times.

Subsequently, the idler gear 25 and the gear ratio 0.71
The driving force is transmitted to the shutter gear 26, and the shutter gear 26 rotates 117.5 °. At this time, since the arm 20 is integrally attached to the shutter gear 26 and the shutter 18 is attached to the arm 20, the shutter 18 is moved to a predetermined position (shutter position) indicated by a broken line in FIG.
18 ').

By configuring such a cam or gear train, it becomes possible to open the shutter 18 to a predetermined position with a small number of input operations. In the present embodiment, since the shutter 18 opens 117.5 ° with respect to the input angle of 17 °, the speed-up movement is 6.9 times.

However, the gear trains 24, 25,
With the configuration of 26, if the phase of the combination of the gears is shifted, the shutter 18 may not be able to be opened to a predetermined angle. Specifically, in the present embodiment, if one tooth shifts due to the combination of the shutter drive gear 24 and the idler gear 25, the shift will be 3.3 ° at the time of input, so that the shutter 18 will only open at 94.7 °. For this purpose, the gear trains 24,
25 and 26 have the following configuration.

As shown in FIG. 10, the shutter driving gear 24
A mark 24p is provided at a predetermined position, and a mark 25p is provided at a position corresponding to the idler gear 25 whose phase with the shutter drive gear 24 is to be matched. On the other hand, the idler gear 25 is provided with a mark 25q in addition to the mark 25p.
A mark 26 is provided at a predetermined position of the shutter gear 26 corresponding to 25q.
q is provided. Then, the mark 24p and the mark 25p are aligned with each other, and the mark 25q and the mark 26q are aligned and assembled, so that the phases of the three gears 24, 25, and 26 can be assembled together.

At this time, if the mark 24p and the mark 25p and the mark 25q and the mark 26q have similar shapes to each other, the visibility of the assembling worker is improved, and it is possible to prevent an assembly error.

As described above, the shutter 18 is opened to a predetermined position by rotating the lock means 22 for fixing the developing device 8Y. On the other hand, the torsion coil spring shown in FIG. Since the force for closing the shutter 18 is always exerted by 20a, if the locking means 22 is left in this state, if any impact or the like is applied to the image forming apparatus, the shutter 18 will not work.
The biasing force of the torsion coil spring 20a for closing the lock means 22 acts on the lock means 22 to release the lock means 22 and the developing device 8Y comes out of the developing rotary 8b, or the developing device 8
During the Y developing process, the shutter 18 may be closed.

Therefore, in the present embodiment, the stopper means 23
Is disposed at a position shown in FIG. 8 in the developing rotary 8b to solve the above problem.

As described above, the rotation of the lock means 22 causes the shutter 18 to rotate from the closed position (see the shutter 18) shown by the solid line in FIG. 8 to the open position (the shutter 18 ') shown by the broken line in FIG. Move. At this time, FIG. 10 and FIG.
As shown by the broken line 11, the boss 18 a provided at the end of the shutter 18 is locked by the locking portion 23 b of the stopper means 23, and the shutter 18 is in the open position (shutter 1
8 ').

Next, the operation of the stopper means 23 will be described.
This will be described in detail with reference to FIG. As described above, the arm 20 supporting the shutter 18 by the rotation operation of the lock unit 22 is provided.
Rotates from the position shown by the solid line in FIG. 11 (see the arm 20) to the position shown by the broken line (see the arm 20 ') via the gear trains 24, 25 and 26.

An end of a shutter 18 is rotatably attached to the arm 20, and a guide member 18b which slides by engaging with a frame of the developing device 8Y is provided at an intermediate portion between both ends of the shutter 18. The shutter 18 moves along the outline S of the frame of the developing device 8Y.

A boss 18a is provided at the end of the shutter 18 on the side to be engaged with the arm 20, and the arm 20 is rotated about the fulcrum 19 so that the boss 18a is Abutment surface 23c of stopper means 23 when it reaches position 18a1
When it slides in contact with and rotates in the same direction, stopper means
The stopper means 23 is gradually depressed against the urging force of the torsion coil spring 23e shown in FIG. 7 provided on the stopper 23 to rotate the stopper means 23 about the shaft 23a in the direction opposite to the arrow g in FIG. When the boss 18a reaches the position 18a2 shown in FIG. 11, the stopper means 23 rotates to the position shown by the broken line in FIG. 11 where the contact surface 23c is the lowest point (see the stopper means 23 ').

Then, the arm 20 further rotates, and the boss
When the position 18a reaches the position 18a3 shown in FIG. 11, the boss 18a separates from the contact surface 23c and falls into the locking portion 23b, whereby the torsion coil spring 23 provided on the stopper means 23 is provided.
The biasing force of e causes the stopper means 23 to rotate about the shaft 23a in the direction of arrow g in FIG.
a is locked by the locking portion 23b of the stopper means 23, the boss 18a is held at the position 18a4 shown in FIG. 11, and the stopper means 23 is at the initial position shown by the solid line in FIG. 11 (see the stopper means 23). ).

With the above arrangement, the shutter 18 can be stopped in a state where the shutter 18 is kept open by the stopper means 23 provided separately and independently of the lock means 22, and the closing force of the shutter 18 is applied to the lock means 22. As a result, even if any impact or the like is applied to the image forming apparatus, the lock unit 22 is disengaged, and the developing device 8Y comes out of the developing rotary 8b or the developing device 8Y.
There is no fear that the shutter 18 will be closed during the Y developing process.

Next, the operation of closing the shutter 18 will be described. As described above, since the shutter 18 is held by the stopper means 23, the shutter 18 does not close even when the lock means 22 is released. Further, as shown in FIG. 11, the stopper means 23 is
Of the developing rotary 8b.

Therefore, the developing device 8Y is connected to the developing rotary 8b.
Then, the boss 18a of the shutter 18 easily comes off the locking portion 23b of the stopper means 23, and the shutter 18 is closed by the biasing force of the torsion coil spring 20a.

With the above configuration, the shutter 18 is closed in conjunction with the detachment operation of the developing device 8Y as a process cartridge, so that the operability is improved.

The locking means 22 and the stopper means 23 as well as the opening / closing mechanism of the shutter 18 are similarly applied to other process cartridges such as the color developing units 8M and 8C, the black developing unit 8B and the drum unit 9. It can be configured.

The intermediate transfer member 3 shown in FIG. 1 has the developing units 8Y, 8M, 8C, 8B during the color image forming operation.
The toner image on the image carrier 4 visualized by (4) is subjected to multiple transfer four times (each image of four colors of yellow, magenta, cyan, and black) in synchronization with the outer peripheral speed of the image carrier 4. The intermediate transfer member 3 rotated in the clockwise direction of FIG. 1 and subjected to the multiple transfer is sandwiched and conveyed by the transfer material P with the transfer roller 31 to which a voltage is applied. The upper and lower color toner images are simultaneously multiplex-transferred.

The intermediate transfer member 3 in this embodiment has a diameter of 1
The outer circumference of a 86 mm aluminum cylinder 32 is covered with an elastic layer 32a such as a medium resistance sponge or medium resistance rubber. The intermediate transfer member 3 is rotatably supported by the apparatus main body 1, and is rotated by being driven by a gear (not shown) integrally fixed to the intermediate transfer member 3.

The cleaning means for the image carrier 4 is such that after the toner image visualized on the image carrier 4 is transferred to the intermediate transfer member 3 by the developing units 8Y, 8M, 8C and 8B, it remains on the image carrier 4. Cleaning the toner,
The cleaned waste toner is stored in the cleaning container 10. The amount of waste toner stored in the cleaning container 10 does not fill the cleaning container 10 earlier than the life of the image carrier 4. Therefore, the cleaning container 10 is simultaneously replaced when the life of the image carrier 4 is replaced. You.

The feeding section feeds the transfer material P to the image forming section 3, and includes a cassette 2 containing a plurality of transfer materials P, a pickup roller 33, a feeding roller 34, and a retard for preventing double feeding. It is configured to include a roller 35, a feeding guide 36, a transport roller 37, a registration roller 38, and the like.

At the time of image formation, the pickup roller 33 is driven to rotate in accordance with the image forming operation, and separates and feeds the transfer material P in the cassette 2 one by one. Via the registration roller 38. During the image forming operation, the registration roller 38 performs a non-rotating operation of stopping the transfer material P in a standby state and a rotating operation of transporting the transfer material P toward the intermediate transfer body 3 in a predetermined sequence. The image and the transfer material P in a certain transfer step are aligned.

The transfer section is composed of a swingable transfer roller 31. The transfer roller 31 is constructed by winding a medium-resistance foam elastic body around the outer periphery of a metal shaft, and is movable vertically in FIG. Driven.

While the four-color toner image is being formed on the intermediate transfer member 3, that is, while the intermediate transfer member 3 is rotated a plurality of times, the transfer roller 31 is moved downward so as not to disturb the image. After the toner image of four colors is formed on the intermediate transfer member 3 after being retracted and separated from the intermediate transfer member 3, the transfer roller 31 is synchronized with the timing of transferring the color image to the transfer material P.
Is pressed against the intermediate transfer member 3 via the transfer material P by a cam member (not shown) at a predetermined pressure. At this time, a bias is applied to the transfer roller 31 at the same time, and the toner image formed on the intermediate transfer body 3 is transferred to the transfer material P.

Here, since the intermediate transfer member 3 and the transfer roller 31 are driven independently of each other, the transfer material P sandwiched between the two is simultaneously subjected to the transfer process and at the same time as the left side of FIG. Is transported at a predetermined speed in the
Sent to

The fixing device 5 includes developing units 8Y, 8M, 8C,
A fixing roller 5a for applying heat to the transfer material P by fixing the toner image formed on the transfer material P via the intermediate transfer body 3 to the toner image formed by the transfer material 8B;
A pressure roller 5b for pressing the transfer material P against the fixing roller 5a; each roller 5a, 5b is a hollow roller;
Heaters 5a1 and 5b1 are respectively provided inside, and the transfer material P is nipped and conveyed by the fixing roller 5a and the pressure roller 5b, and the toner image is fixed on the transfer material P by applying heat and pressure. Is done.

[0090]

Since the present invention has the above-described configuration and operation, the operation of mounting the process cartridge in the image forming apparatus main body and the operation of opening and closing the shutter of the process cartridge are performed separately. It is possible to simplify the configuration of the main body of the part where the process cartridge is inserted into the main body of the image forming apparatus and the configuration of the process cartridge, to save space and cost, and to make each operation independent. Can be performed more reliably, and erroneous operations by the user can be prevented.

Further, operability can be improved by interlocking the operation of operating the locking means for preventing the process cartridge from being detached in the image forming apparatus main body with the opening operation of the shutter of the process cartridge. I can do it.

Further, by receiving the urging force applied in the closing direction of the shutter by stopper means provided separately from the locking means and holding the shutter open, it is possible to prevent the urging force from being applied to the locking means. It is possible to prevent. This makes it possible to prevent problems such as detachment of the lock means due to an impact or the like, or the shutter being closed by mistake, with a simple configuration.

Further, by arranging the stopper means at a position which does not interfere with the mounting / removing direction of the process cartridge, the shutter which is kept at the open position only by releasing the locking means can move the process cartridge to the main assembly of the image forming apparatus. By releasing from the shutter, the shutter is released from the stopper means, and the shutter is closed by the urging means of the shutter mechanism. As a result, when the user detaches the process cartridge from the image forming apparatus main body, the shutter automatically closes.
User operations are simplified.

Further, by making the opening and closing operation of the shutter a speed-up movement by the gear train, the swing mechanism of the shutter can be saved in space and the amount of operation by the user can be minimized.

Further, by providing a mark at the phase matching position of the gear train and assembling the same, the assembly operation of the process cartridge can be performed easily and reliably, and the swinging failure of the shutter due to the phase shift of the gear train can be prevented.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view illustrating a configuration of an image forming apparatus according to the present invention.

FIG. 2 shows a process cartridge according to the present invention.
FIG. 3 is a perspective view illustrating a configuration in which a shutter is omitted.

FIG. 3 is a perspective view illustrating a state in which a process cartridge is mounted on an image forming apparatus main body.

FIG. 4 is a cross-sectional view showing an opening and closing operation of a shutter provided in a process cartridge.

FIG. 5 is a perspective view illustrating a state in which the process cartridge is mounted on the image forming apparatus main body and locked by locking means.

FIG. 6 is a perspective view showing a configuration of a stopper means.

FIG. 7 is a perspective view showing a configuration of a stopper means.

FIG. 8 is a perspective view showing a positional relationship among a shutter, a lock unit, and a stopper unit and a state of an interlocking operation thereof.

FIG. 9 is a diagram illustrating a positional relationship between an arm supporting a shutter and stopper means.

FIG. 10 is a cross-sectional explanatory view illustrating a state of an interlocking operation of a shutter, a lock unit, and a stopper unit.

FIG. 11 is an explanatory cross-sectional view showing a state of an interlocking operation between a shutter and a stopper means.

FIG. 12 is a diagram illustrating a conventional example.

FIG. 13 is a diagram illustrating a conventional example.

FIG. 14 is a diagram illustrating a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus main body, 2 ... Cassette, 3 ... Intermediate transfer body, 4 ... Image carrier, 5 ... Fixing device, 5a ... Fixing roller,
5b: pressure roller, 5a1, 5b1: heater, 6: discharge roller, 7: discharge unit, 8: image forming unit, 8B: black developing device, 8Y: yellow developing device, 8M: magenta developing device, 8
C: Cyan developing unit, 8BS, 8YS, 8MS, 8CS: Sleeve, 8YR, 8MR, 8CR: Supply roller, 8YB, 8MB, 8CB
... Developing blade, 8a ... Shaft, 8b ... Developing rotary, 8b
1 ... side plate, 8b2 ... opening, 8c ... protrusion, 9 ... drum unit, 10 ... cleaning container, 11 ... cleaner blade,
12 ... primary charging means, 13 ... scanner unit, 14 ... polygon mirror, 15 ... imaging lens, 16 ... reflection mirror, 18 ... shutter, 18a ... boss, 19 ... fulcrum, 20 ... arm, 20a ... torsion coil spring, 21 ... Flange, 22 ... Locking means, 22a ...
Shaft, 22b lock cam, 23 stopper means, 23a
Shaft, 23b locking part, 23c contact surface, 23d regulating means, 23
e: torsion coil spring, 24: shutter drive gear, 24a
... shaft, 24b ... cam, 24p ... mark, 25 ... idler gear, 25
p, 25q: mark, 26: shutter gear, 26q: mark, 31
... Transfer roller, 32 ... Cylinder, 32a ... Elastic layer, 33 ... Pickup roller, 34 ... Feed roller, 35 ... Retard roller, 36 ... Feed guide, 37 ... Transport roller, 38 ... Register roller, P ... Transfer material

Claims (6)

[Claims] An electrophotographic photosensitive member, a charging unit for charging the surface of the electrophotographic photosensitive member, a cleaning unit for removing a residue on the surface of the electrophotographic photosensitive member, and A cleaning container for containing;
The electrophotographic photosensitive member, the charging unit, a developing rotator for supplying a developer to the electrophotographic photosensitive member to develop a latent image formed on the electrophotographic photosensitive member, and A supply rotator for supplying the developer to the surface, a developing blade for applying the developer in a thin layer on the surface of the developing rotator, and for applying a charge to the developer; A process cartridge having an openable and closable shutter which is always urged in a direction of a closed position by urging means to protect at least two portions of the developer container while integrating at least two components of the developer container. In the image forming apparatus configured to be detachable in the axial direction with respect to the image forming apparatus main body, the mounting operation of the process cartridge to the image forming apparatus main body and the opening and closing operation of the shutter are performed. An image forming apparatus characterized in that it can be operated independently. 2. The image forming apparatus according to claim 1, further comprising: a lock unit for preventing the process cartridge from coming off in a mounting direction after the process cartridge is mounted on the image forming apparatus main body. The lock unit is provided on the process cartridge by an operation when the lock unit operates. The image forming apparatus according to claim 1, wherein the shutter is configured to swing from a closed position to an open position. 3. A stopper means for holding the shutter at an open position independently of the lock means, wherein the shutter is moved to the open position by the operation of the lock means. And holding the shutter at the open position against the urging force of the urging means so that the urging force of the urging means does not act on the lock means. 3. The image forming apparatus according to 2. 4. The stopper means is configured not to interfere when the process cartridge is detached from the image forming apparatus main body, and the stopper means is provided when the process cartridge is detached from the image forming apparatus main body. 4. The image forming apparatus according to claim 3, wherein when the shutter is disengaged from the shutter, the shutter swings to a closed position by an urging force of the urging means. 5. The process cartridge detachably mounted on the image forming apparatus according to claim 1, wherein the swing operation of the shutter from a closed position to an open position is increased by a gear train. A process cartridge configured to operate by a rapid movement. 6. The process cartridge according to claim 5, wherein a mark for assembling the gear train by matching the phase of the gear train is provided.