JP2001235994A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device enabling the prevention of leakage of waste toner. SOLUTION: An image forming device 50 has a process cartridge 31 attachable to and detachable from a device main body 45. The process cartridge 31 is equipped at least with an intermediate transfer body 10 for carrying a toner image, a cleaning blade 16A for removing the waste toner of the intermediate transfer body 10, and a waste toner recovery part 16c for recovering the waste toner removed by the cleaning blade 16A. Furthermore, the process cartridge 31 is equipped with a shield member 33 movable to the closed position for filling the space M between the waste toner recovery part 16c and intermediate transfer body 10, and to the open position for opening the space M between the waste toner recovery part 16c and intermediate transfer bodies 10. When the process cartridge 31 is loaded in the device main body 45, the shield member 33 moves from the closed position to the open position in conjunction with the loading of the process cartridge 31. When the process cartridge 31 is detached from the device main body 45, the shield member 33 moves from the open position to the closed position in conjunction with detachment of the process cartridge.

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 such as a printer, a copying machine, a facsimile, and the like, and more particularly, to an image forming apparatus having a process cartridge detachably mounted on an apparatus main body.

[0002]

2. Description of the Related Art Generally, in a color image forming apparatus using an intermediate transfer body (image carrier) or a color image forming apparatus in which a plurality of color toners are superimposed on a photosensitive body and collectively transferred to a transfer material, the intermediate transfer is performed. There is a process cartridge in which a cleaning device for removing waste toner remaining on the body and the intermediate transfer member is integrally formed as a process cartridge, and the process cartridge is provided detachably with respect to the image forming apparatus main body.

In such a color image forming apparatus, since a plurality of color toner images are sequentially transferred onto an intermediate transfer member, a cleaning member cannot be brought into contact with an image carrier during image formation. Cleaning member can be moved toward and away from the intermediate transfer member. Similarly, in the waste toner collecting section, the waste toner collecting section cannot be brought into contact with the intermediate transfer body during image formation.

[0004]

However, when the waste toner collecting section is not provided so as to be able to approach and separate from the intermediate transfer body, a gap is always provided between the waste toner collecting section and the intermediate transfer body. Are formed. Therefore, depending on the orientation of the process cartridge, such as when the process cartridge is removed from the apparatus main body and the removed process cartridge is turned upside down, the waste toner collected in the waste toner collecting unit may be
There is a problem that the waste toner is leaked from a gap between the waste toner collecting unit and the intermediate transfer body.

Accordingly, an object of the present invention is to provide an image forming apparatus capable of preventing waste toner from leaking.

[0006]

According to the first aspect of the present invention, there is provided a process cartridge detachably mountable to an apparatus main body, wherein the process cartridge is in contact with an image carrier for carrying a toner image and the image carrier. In an image forming apparatus including at least a cleaning member that is detachably provided and removes waste toner of the image carrier in contact with the image carrier, and a waste toner collecting unit that collects waste toner removed by the cleaning member, the process cartridge includes: A closing member that closes a gap between the waste toner collecting unit and the image carrier, and a shielding member that can move to an open position that opens a gap between the waste toner collecting unit and the image carrier. When the process cartridge is moved from the closed position to the open position in conjunction with the mounting of the process cartridge when it is mounted on the main body, and the process cartridge is detached from the main body. To in association with the detachment of the process cartridge from an open position wherein it points to the closed position.

According to the first aspect of the present invention, when the process cartridge is mounted on the apparatus main body, the shielding member moves from the closed position to the open position, and a gap is formed between the waste toner collecting section and the image carrier. . After the process cartridge is mounted on the apparatus main body, when the image carrier carries the toner image, the cleaning member is separated from the image carrier, and after the toner image on the image carrier is transferred, the cleaning member The waste toner on the image carrier is removed by contacting the image carrier. The waste toner removed by the cleaning member is collected by a waste toner collection unit.

On the other hand, when the process cartridge is removed from the apparatus main body, the shielding member moves from the open position to the closed position,
Close the gap between the waste toner collecting unit and the image carrier. Therefore, regardless of the orientation of the process cartridge, such as holding the process cartridge upside down, it is possible to prevent waste toner from leaking from the gap between the waste toner collecting unit and the image carrier, and to prevent contamination of the surroundings.

According to a second aspect of the present invention, in the first aspect, a contact portion of the shielding member with the image carrier is provided.
An elastic member is provided.

[0010] According to the second aspect of the present invention, the first aspect is provided.
In addition to the effects similar to those of the invention described in (1), the elastic member reduces the impact at the time of contact with the image carrier, so that it is possible to prevent the image carrier from being damaged. Also, at the time of contact,
Since the elastic member is in close contact with the image carrier, the sealing property with the image carrier can be improved, and leakage of waste toner can be further prevented.

[0011] The invention described in claim 3 is the invention according to claim 1 or 2.
In the invention described in (1), an opposing member is provided at a position opposing the shielding member, and when the shielding member is at the closed position, the image carrier is sandwiched between the shielding member and the opposing member.

According to the third aspect of the present invention, the first aspect is provided.
Or the same effect as the invention described in 2 above, and the image carrier is flattened along the opposing member by sandwiching the image carrier between the shielding member and the opposing member. The sealing performance with the image carrier can be further improved.

According to a fourth aspect of the present invention, in the third aspect, the opposing member is not in contact with the image carrier when the process cartridge is mounted on the apparatus main body. And

According to the fourth aspect of the present invention, there is provided the third aspect.
When the process cartridge is mounted on the apparatus main body, the shielding member moves from the closed position to the open position, and this movement pushes the shielding member against the opposing member. The image carrier moves away from the opposing member. Therefore, during image formation, the opposing member does not come into contact with the image carrier, so that it is possible to prevent the image carrier from being damaged, and to prevent the life of the image carrier from being shortened.

[0015]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. First, a first embodiment will be described with reference to FIGS. FIG.
As shown in FIG. 1, an image forming apparatus 50 is a color image forming apparatus 50 including an intermediate transfer belt 10 as an intermediate transfer body. It has a color scanner for converting into (image information) and a laser writing device 5 as exposure means.

The writing device 5 converts the color image data from the color scanner into an optical signal, performs optical writing corresponding to the original image, and places the image on the surface of the flexible photosensitive belt 1 as an image carrier. Form an electrostatic latent image. That is, a laser beam L generated by a semiconductor laser (not shown) is adjusted in optical path and scanning by an optical device such as an f / θ lens and a reflection mirror according to image data, reaches the photosensitive belt 1, and is charged. Scanning exposure based on image information is performed on the photoreceptor belt 1 charged by the charging charger 4 as a means to form an electrostatic latent image.

The photosensitive belt 1 is rotatably supported by rotating rollers 2 and 3, and rotates clockwise, for example, as shown by an arrow A in the figure. Around the photoreceptor belt 1, a photoreceptor cleaning device 15 having a cleaning blade 15A and a waste toner collecting container 15c, a charging charger 4, and a color developing device 6 as a developing unit
And an intermediate transfer belt 10.

The color developing device 6 integrally forms four developing devices 6a, 6b, 6c and 6d having yellow (magenta), cyan and black developers (toners). Each of the developing devices 6a to 6d includes a developing sleeve 7a to 7d for supplying a developer of each color to the photoreceptor belt 1 for visualizing an electrostatic latent image on the photoreceptor belt 1; And the developing paddles 9a to 9d which rotate to perform the operation. In this embodiment, any one of the developing devices 6a to 6d moves to a position where development is possible in synchronization with the timing of the corresponding color.

The intermediate transfer belt 10 includes a rotating roller 11,
12 rotatably supported, and rotates counterclockwise as indicated by arrow B in the figure. Intermediate transfer belt 10
And the photoreceptor belt 1 are in contact at a contact portion T. A conductive bias roller 13 is in contact with the back surface of the intermediate transfer belt 10 under predetermined conditions at the contact portion T,
The toner image on the photosensitive belt 1 is transferred to the surface of the intermediate transfer belt 10 by the bias roller 13.

An intermediate transfer member cleaning device 16 for cleaning the surface of the intermediate transfer belt 10 is provided near the rotary roller 11 that supports the intermediate transfer belt 10. This intermediate transfer body cleaning device 16
Cleaning blade (cleaning member) 16A
Is movable toward and away from the intermediate transfer belt 10 via a not-shown arm.

When the toner image is transferred from the photosensitive belt 1 to the intermediate transfer belt 10 (during image formation), the cleaning blade 16A
After the toner image is transferred from the intermediate transfer belt 10 to the transfer paper 17A, the toner image contacts the intermediate transfer belt 10 to scrape off the waste toner on the intermediate transfer belt 10.

The transfer paper 17A to which the toner image is transferred is fed from a paper feed cassette 17 to a paper feed roller 18 and a transport roller pair 19.
A, 19B and the registration roller pair 2
A nip (transfer portion) N between the intermediate transfer belt 10 and the transfer roller 14 at a predetermined timing according to 0A and 20B.
Sent to.

On the other hand, in the stage before the transfer of the transfer paper 17A, toner images of a predetermined color are sequentially formed on the photoreceptor belt 1, and each time the toner images of each color are the same on the intermediate transfer belt 10. The images are sequentially transferred to the respective positions (each color is transferred every time the intermediate transfer belt 10 makes one rotation). In this case, the photoreceptor belt 1 is cleaned for each color to prepare for the formation of the next color.

The plurality of color toner images sequentially transferred and superimposed on the intermediate transfer belt 10 are collectively transferred onto a transfer paper 17A sent to a nip portion N between the transfer roller 14 and the transfer roller. Transfer paper 17A on which a plurality of color toner images are collectively transferred
Is sent to the fixing device 80, the toner image is fixed on the transfer sheet 27A by the fixing roller 80A and the pressure roller 80B, and is discharged as a print image to the discharge stack 82 by the discharge roller pairs 81A and 81B. .

Further, the cleaning blades 15A, 16
Waste toner scraped off from the photoreceptor belt 1 and the intermediate transfer belt 10 by A is stored in a collection container 15c. In this case, the waste toner scraped off by the cleaning blade 16A is conveyed in the forward direction in the figure by the auger 16b provided in the waste toner collecting section 16c of the intermediate transfer body cleaning device 16, and further forward of the process cartridge 31 described later. The transfer unit (not shown) provided on the side surface is configured to be transferred to the collection container 15c. In addition, the collection container 15c is appropriately replaced according to the amount of waste toner stored. That is, when a predetermined amount or more of waste toner is stored in the collection container 15c,
By replacing the process cartridge 31,
The life of the process cartridge 31 can be extended.

On the other hand, the structure of the apparatus main body 45 is composed of the main body frame 21 and the front frame 8 from which the transfer path 40 for the transfer paper 17A can be opened.
1, a paper feed cassette 17 is arranged, the color developing device 6 and the process cartridge 31 are exchangeably arranged inside the main body, and a fixing device 80 is arranged further thereabove. , A discharge stack 82.

The front frame 8 is supported so as to be openable and closable about a rotation support shaft 21A provided on the main body frame 21, and is normally held in a closed state as shown in FIG. When a jam occurs in the transfer path 40 of the transfer paper 17A, as shown in FIG. 2, the lock mechanism (not shown) of the front frame 8 is released to open the front frame 8. The front frame 8 holds a pair of conveyance rollers 19A, a registration roller 20A, a transfer roller 14 and the like which constitute a part of the transfer path 40 of the transfer paper. When the front frame 8 is opened, the transfer paper 17A The transport path 40 is exposed so that the jam processing can be easily performed. At this time, the other image forming system devices are immobile, so that scattering and leakage of toner are prevented.

The process cartridge 31 integrally incorporates the photoreceptor belt 1, the charging charger 4, the intermediate transfer belt 10, the respective cleaning devices 15, 16 and the like, and the collection container 15c is exchangeably incorporated into the process cartridge 31. And can be replaced at the end of its life. The process cartridge 31 is provided with a shielding member 33 for closing the gap M (see FIG. 3) between the waste toner collecting section 16c and the intermediate transfer body 10 when the process cartridge 31 is removed from the apparatus main body 45. . The registration roller 2 of the process cartridge 31
The case exterior portion 31A on the 0B side also has a function as a transfer paper transport guide.

Further, similarly to the front frame 8, the process cartridge 31 is held by a process cartridge holding portion 41 which is rotatable around a rotation support shaft 21A provided on the main body frame 21. When removing the process cartridge 31 from the apparatus main body 45, as shown in FIG. 3, the process cartridge 31 is raised toward the front frame 8 in an open state and is pulled out upward. The process cartridge 31 has a guide portion 31B inserted into a groove provided on both inner side surfaces of the holding member 41, and the guide portion 31B is inserted and removed along the groove of the holding member. ing.

FIG. 4 is a sectional view showing the vicinity of the cleaning device when the process cartridge is taken out of the apparatus main body, and FIG. 5 is a sectional view showing the vicinity of the cleaning device when the process cartridge is mounted on the apparatus main body. FIG. 6 is a cross-sectional view showing a state in which the process cartridge removed from the apparatus main body is placed in a normal state. 4 and 5, the vicinity of the cleaning member 16A of the cleaning device 16 is omitted for simplification.

As shown in FIG. 4 to FIG.
Is provided along the outer wall of the waste toner collecting section 16c of the cleaning device 16. The shielding member 33 is a lever 52
As a result, the process cartridge 3
Interlocking with the attachment / detachment of the first transfer member 1, it can be moved to a closed position (the position in FIG. 4) for closing the gap M between the waste toner collecting unit 16c and the intermediate transfer body 10 and an open position (the position in FIG. It has become.

The shielding member 33 is provided for the process cartridge 3.
It has pins 33a and 33b inserted into a long hole 31c formed on the side surface of one housing, and is provided so as to be slidable in the longitudinal direction of the long hole 31c. An elastic member 3 is provided at a contact portion of the shielding member 33 with the intermediate transfer body 10.
5, the elastic member 35 is in close contact with the intermediate transfer member 10 when the shielding member 33 is at the closed position. Therefore, the sealing property for the intermediate transfer body 10 can be improved. Further, since the elastic member 35 reduces the impact at the time of contact with the intermediate transfer body 10, it is possible to prevent the image carrier from being damaged.

The lever 52 is rotatable about a rotation shaft 52a. A biasing member 53 such as a spring is attached to one end 52c of the lever 52, and the other end of the lever 52 is mounted. A long hole 52b into which one pin 52b of the shielding member 33 is inserted is formed in 52d.

As shown in FIG. 4, one end of the urging member 53 is attached to one end 52c of the lever 52, and the other end of the urging member is attached to the side surface of the housing of the process cartridge 31. The biasing member 53 includes the lever 5
The second end 52c is urged in the direction of arrow C. By the urging force of the urging member 53, the lever 52
Rotates around the rotation shaft 52a in the counterclockwise direction in the figure, and the shielding member 33 moves toward the closed position.

As shown in FIG. 5, one end 52c of the lever 52 is connected to a fixed shaft 2 provided on the main body frame 21.
By contact with 1B, it moves in the direction of arrow D against the urging force of the urging member 53. As a result, the lever 52 rotates clockwise in the figure around the rotation shaft 52a, and the shielding member 33 moves toward the open position.

Next, the operation of the present embodiment will be described based on the configuration described above. When the process cartridge 33 is set in the apparatus main body 45, as shown in FIG. 3, the front frame 8 of the apparatus main body 45 is released, and the process cartridge 31 is inserted from above into the holding member 41.
This is performed by rotating counterclockwise in the figure around a rotation support shaft 21A provided on the main body frame 21 and setting it to a proper position (image forming position).

At this time, as shown in FIG. 5, one end 52c of the lever 52 comes into contact with the fixed shaft 21B provided on the main body frame 21, so that the lever 52 is rotated.
It rotates around arrow 2a in the direction of arrow D. By the rotation of the lever 52, the shielding member 33 is separated from the intermediate transfer body 10, and the shielding member 33 is located at the open position.

On the other hand, when the process cartridge 31 is removed from the apparatus main body 45 (separated), as shown in FIG. 4, the lever 52 released from contact with the fixed shaft 21B is released.
Is rotated in the direction of arrow C by the urging force of the urging member 53.
By the rotation of the lever 52, the shielding member 33 moves toward the intermediate transfer body 10, contacts the intermediate transfer body 10 (the shielding member 33 is located at the closed position), and the waste toner collecting section 16c.
The gap M between the intermediate transfer member 10 and the intermediate transfer member 10.

The process cartridge 31 taken out of the apparatus main body 45 is normally placed in a normal state in which the cleaning device 16 is located below the intermediate transfer body 10, as shown in FIG. However, the process cartridge 31 is placed upside down (the cleaning device 16 is
In the case of “0”, the waste toner stored in the waste toner collecting unit 16 c falls onto the intermediate transfer body 10.
In this state, when the process cartridge 31 is placed in the normal state, in the conventional configuration without the shielding member 33, the waste toner dropped on the intermediate transfer body 10 is removed by the waste toner collecting section 16c and the intermediate transfer body 10 However, in the present embodiment, since the gap M is closed by the shielding member 33, the leakage of the waste toner can be prevented.

By providing the shielding member 33 in this manner, no matter what direction the process cartridge 31 is held, the waste toner from the waste toner collecting portion 16c spills out of the process cartridge 31 from the gap M. Can be prevented, and the surrounding dirt can be prevented.

Next, other embodiments will be described. In the description, the same parts as those described above are denoted by the same parts, and the description thereof is omitted.

FIG. 7 is a perspective view showing the vicinity of the cleaning device according to the second embodiment, and FIG. 8 is a sectional view showing the vicinity of the cleaning device when the process device is mounted on the device main body. . As shown in FIGS. 7 and 8,
The second embodiment is different from the first embodiment in that an opposing member 55 is provided inside the intermediate transfer body 10.

The opposing member 55 is provided at a position opposing the shielding member 33 with the intermediate transfer member 10 interposed therebetween. As shown in FIG. 7, when the process cartridge 31 is mounted on the apparatus main body (shielding). (When the member 33 is at the open position) and is provided separately from the intermediate transfer body 10.

That is, when the process cartridge 31 is mounted on the apparatus main body 45, the shielding member 33 moves from the closed position to the open position, and this movement pushes the shielding member 33 toward the opposing member 55. The intermediate transfer member 10 is separated from the facing member 55. Therefore, during image formation,
Since the opposing member 55 does not contact the intermediate transfer member 10, abrasion due to sliding with the opposing member 55 inside the intermediate transfer member 10 can be prevented, and a reduction in the life of the intermediate transfer member 10 can be prevented.

On the other hand, when the process cartridge 31 is pulled out from the apparatus main body 45, the shielding member 33 moves from the open position to the closed position, and the intermediate transfer body 10 is pressed toward the facing member 55. As shown in FIG. 8, the intermediate transfer member 1 is
0 is pinched. Therefore, the intermediate transfer body 10 is
, The shielding member 33 and the intermediate transfer member 1
0, and the leakage of the waste toner from the gap M can be further prevented.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the present embodiment, the intermediate transfer member is used as the image carrier, but may be applied to the photoreceptor belt 1. Further, the present invention may be applied to not only an endless belt-shaped image carrier but also a drum-shaped image carrier.

In the present embodiment, the cleaning blade 16A is used as the cleaning member. However, for example, a cleaning brush or the like, or both a cleaning blade and a cleaning brush may be used.

[0048]

According to the first aspect of the present invention, the shielding member closes the gap between the waste toner collecting section and the image carrier, so that the waste toner collecting section and the image carrier can be arranged in any orientation of the process cartridge. Of the waste toner can be prevented from leaking from the gap with the surroundings, and the surrounding dirt can be prevented.

According to the second aspect of the present invention, the same effect as that of the first aspect of the invention is provided, and the elastic member reduces the impact at the time of contact with the image carrier. Can be prevented from being damaged. Further, at the time of contact, the elastic member is in close contact with the image carrier, so that the sealing performance with the image carrier can be improved, and leakage of waste toner can be further prevented.

According to the third aspect of the present invention, the same effects as those of the first or second aspect of the invention are provided, and the image carrier is sandwiched between the shielding member and the facing member.
The sealing property between the shielding member and the image carrier can be further improved.

According to the fourth aspect of the invention, the same effects as those of the third aspect of the invention can be obtained, and the image bearing member can be prevented from being damaged because the opposing member does not contact the image carrier during image formation. Thus, the life of the image carrier can be prevented from being shortened.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing an image forming apparatus according to the present invention.

FIG. 2 is a diagram illustrating a state in which a front frame of the image forming apparatus in FIG. 1 is opened.

FIG. 3 is a diagram illustrating attachment and detachment of a process cartridge to and from the apparatus main body.

FIG. 4 is a sectional view showing the vicinity of the cleaning device when the process cartridge is taken out from the apparatus main body.

FIG. 5 is a cross-sectional view showing the vicinity of the cleaning device when a process cartridge is mounted on the apparatus main body.

FIG. 6 is a cross-sectional view illustrating a state where the process cartridge taken out of the apparatus main body is placed in a normal state.

FIG. 7 is a perspective view showing the vicinity of a cleaning device according to a second embodiment.

FIG. 8 is a cross-sectional view showing the vicinity of the cleaning device when the process device is mounted on the device main body.

[Explanation of symbols]

 Reference Signs List 10 Intermediate transfer member (image carrier) 16A Cleaning blade (cleaning member) 16c Waste toner collecting container 31 Process cartridge 33 Shielding member 35 Elastic member 45 Device main body 50 Image forming device 55 Opposing member

Claims (4)

[Claims] A process cartridge detachably mountable to an apparatus main body, wherein the process cartridge is provided with an image carrier for carrying a toner image, and is detachably provided on the image carrier, and the image carrier is in contact with the image carrier. In an image forming apparatus including at least a cleaning member that removes waste toner from a body and a waste toner collecting unit that collects waste toner removed by the cleaning member, the process cartridge includes a gap between the waste toner collecting unit and the image carrier. A shielding member movable between a closed position for closing and an open position for opening a gap between the waste toner collecting unit and the image carrier. The shielding member is interlocked with the mounting of the process cartridge when the process cartridge is mounted on the apparatus main body. When the process cartridge is moved from the closed position to the open position and the process cartridge is An image forming apparatus comprising moving to the closed position from the position. 2. The image forming apparatus according to claim 1, wherein an elastic member is provided at a contact portion of the shielding member with the image carrier. 3. The image carrier has an endless belt shape.
2. The image bearing member according to claim 1, further comprising: a facing member provided inside the image carrier and facing the shielding member, wherein the shielding member and the facing member sandwich the image carrier when the shielding member is in the closed position. 3. The image forming apparatus according to 2. 4. The image forming apparatus according to claim 3, wherein the opposing member is not in contact with the image carrier when the process cartridge is mounted on the apparatus main body.