JP2008225357A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a filling factor of waste toner into a container by preventing the waste toner from being unevenly accumulated in the container, in a configuration having an endless belt-like second image carrier superimposing toners on a plurality of first image carriers, a cleaning member removing residual toner on the second image carrier and the container in which the toner removed by the cleaning member directly drops by gravity and is stored. <P>SOLUTION: The width L2 of the opening 19b-1 of the container 19b is larger than the width L1 of the cleaning member 19a, the container 19b is movable in its longitudinal direction, while keeping such a relationship that the longitudinal width of the cleaning member 19a is always positioned in the range of the opening 19b-1, and a stop position after the movement is changed to store the dropped toner. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as an electrophotographic copying apparatus, a facsimile, a printer, a plotter, a multifunction peripheral, and a printing apparatus, and more particularly to an image forming apparatus provided with a container for waste toner.

Conventionally, when adopting a configuration in which waste toner is stored in a container by free fall, many proposals have been made to impart vibration to the container and make it flat in order to increase the filling rate in the container.
For example, in Patent Document 1, a waste toner container is accommodated in a waste toner container accommodation member, and a waste toner container vibration means including a first vibration means and a second vibration means is provided around the waste toner container, and the first vibration means is a waste. The toner container housing member is moved to the left by a motor and a cam, and is urged to the right by an urging means, whereby the waste toner T is vibrated in a horizontal direction to flatten the waste toner T accumulated in a mountain shape. . Further, the second vibration means gives a vibration having a smaller amplitude than the vibration of the first vibration means in the direction perpendicular to the waste toner accommodating member by the motor and the cam, and removes the air contained in the waste toner to increase the filling rate. It is configured. However, in order to move the waste toner accumulated in a mountain shape by the motor and the cam and make it flat, a corresponding driving energy is required.

  In Patent Document 2, forward / reverse transmission means for inverting and connecting the conveyance drive mechanism and the vibration drive mechanism is provided, and the waste toner storage container is vibrated simply by reverse rotation using a common drive source provided in the paper supply means. With this configuration, a dedicated drive source is omitted, a complicated switching mechanism and a control device are not required, and the conveyance drive unit is used in common, and a reverse operation is performed when vibration is applied.

In Patent Document 3, waste toner is collected by a cleaning device provided for a photosensitive drum, and is transported toward a waste toner box by a transport unit. The waste toner box is provided with means for applying a tapping action in conjunction with the rotation of the toner bottle, and when the toner is supplied to the developing device, the waste toner box is vibrated by the rotation of the toner bottle. An action is performed so that the waste toner does not collect in an uneven position inside. However, since the rotation of the toner bottle is limited only when the toner is replenished, the timing is irregular, which is not preferable.
In Patent Document 4, the waste toner container is vibrated in conjunction with the operation of pulling out the paper feed cassette from the image forming apparatus, and the waste toner in the container is leveled. This is because there is a possibility that variations in operation frequency, timing, etc. occur between users.

JP 2006-119336 A JP 2000-194243 A JP 2005-331832 A Japanese Patent Laid-Open No. 2001-312190

  The technology described in each of the above-mentioned patent documents applies an external force such as vibration to the toner loaded in a mountain shape in the container to equalize the toner. However, it is necessary to have an energy suitable for leveling the state already loaded in a mountain shape by the impact applied to the container.

  The present invention has been made under the circumstances described above. The first is to prevent a state in which the container is loaded in a container in an unbalanced manner, and moreover, a periodic operation can be performed without particularly providing a dedicated drive source. The purpose is to level the waste toner efficiently by vibrating the container.

In order to achieve the above object, an invention according to claim 1 is directed to an endless belt-like second image carrier that superimposes toners on a plurality of first image carriers and residual toner on the second image carrier. A cleaning member for removing the toner and a container for storing the toner removed by the cleaning member by dropping it directly by gravity, and the opening for collecting the toner in the container has a width in the longitudinal direction of the cleaning member. The container is movable in the longitudinal direction while maintaining a relationship that is long in the longitudinal direction and the width in the longitudinal direction of the cleaning member is always within the range of the opening, and the falling toner is changed by changing the stop position after the movement. Was decided to accommodate.
According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the container is moved based on print position information of the image.
According to a third aspect of the present invention, in the image forming apparatus according to the first aspect, the movement (position, movement timing) of the container is performed based on pixel number information of an image formed on each of the plurality of image carriers. did.
According to a fourth aspect of the present invention, in the image forming apparatus according to the first aspect, the movement (position, timing) of the container is performed based on toner amount information on the second image carrier. According to a fifth aspect of the present invention, there is provided the image forming apparatus according to the first aspect, wherein the print position information of the image, the pixel number information of the image formed on each of the plurality of image carriers, and the toner on the second image carrier. It was decided to be executed based on information obtained by combining at least two pieces of quantity information.
The invention according to claim 6 is the image forming apparatus according to any one of (1) to (5), wherein the movement of the container is performed in the region in which the opening is divided into a plurality of portions at least equally in the moving direction. The determination is made based on the magnitude relationship between the amount of toner dropped by the cleaning member.
According to a seventh aspect of the present invention, in the image forming apparatus according to any one of the first to sixth aspects, the member operating in the image forming apparatus is a vibration applying unit, and the member is operated in conjunction with the movement of the vibration applying unit. The container was vibrated to make the upper surface of the toner contained in the container uniform.
According to an eighth aspect of the present invention, in the image forming apparatus according to the seventh aspect, the second image carrier is supported by at least two support rollers, the support rollers include tension rollers, and the container includes The position is determined with respect to the tension roller as the vibration applying means.
According to a ninth aspect of the present invention, in the image forming apparatus according to the seventh aspect, a belt device including the second image carrier can be brought into contact with and separated from the first image carrier, and the vibration application is performed. As the means, vibration is applied to the container in conjunction with the contact / separation operation of the belt device.
According to a tenth aspect of the present invention, in the image forming apparatus according to the seventh aspect, the image forming apparatus further includes a transfer unit that transfers a toner image from the second image carrier to a sheet-like medium, and the transfer unit is The image bearing member can be brought into and out of contact with the second image carrier, and the vibration is applied to the container in conjunction with the contact and separation operation of the transfer unit as the vibration applying unit.
According to an eleventh aspect of the present invention, in the image forming apparatus, the upper surface of the toner contained in the container is made uniform by applying vibration to the container in conjunction with movement of a member operating in the image forming apparatus. The upper surface of the toner in the container is made uniform by combining at least two vibration applying means described in No. 10.
The invention according to claim 12 comprises any combination of claims 1 to 6 and claims 7 to 11.

  According to the present invention, the first is to increase the filling rate by preventing the state of being loaded in the container by shifting the position of the container, and further without providing a dedicated drive source. By synchronizing with the periodic operation, the container can be vibrated and the waste toner can be leveled efficiently.

[1] Image Forming Apparatus Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a schematic structure of an electrophotographic apparatus of a tandem type indirect transfer system as an example of the image forming apparatus of the present invention.

  In FIG. 1, an intermediate transfer member 10 is provided as a second image carrier in the form of an endless belt at the left and right and upper and lower centers of the main body 1 of the electrophotographic apparatus. The intermediate transfer member 10 may have either a multilayer structure or a single layer structure. In the case of a multilayer structure, the base layer is made of, for example, a fluororesin or PVDF sheet with little elongation, and a polyimide resin, and the surface is covered with a smooth coat layer such as a fluorine resin. Some use materials such as PC and polyimide. In the present invention, the material of the intermediate transfer member 10 is not particularly limited.

  As shown in FIG. 1, the intermediate transfer member 10 is hung around the support rollers 12 and 13 at both ends in the left-right direction, and is further hung around the support rollers 14 and 15 disposed below the support rollers 12 and 13. As shown by the arrows in the figure, it is configured to be driven to rotate counterclockwise.

  In the illustrated example, an intermediate transfer member cleaning device 19 for removing residual toner remaining on the intermediate transfer member 10 after image transfer is provided on the left of the support roller 13. The intermediate transfer body cleaning device 19 includes a blade 19a as a cleaning member made of a material such as urethane that comes into contact with the support roller 13 via the intermediate transfer body 10, and a container 19b that directly stores toner that is removed by the blade 19a and falls. It includes support means (not shown) for the blade 19a, means (not shown) for moving the container 19b, and the like. The blade 19 a is in contact with the rotation direction of the intermediate transfer member 10 in the counter direction.

  On the intermediate transfer member 10 stretched between the support roller 14 and the support roller 15, four image forming units [K], [C] of black, cyan, magenta, and yellow are sequentially arranged from the downstream side along the conveyance direction. ], [M], [Y] are arranged side by side to constitute a tandem image forming apparatus. An exposure device (not shown) is provided under the tandem image forming apparatus.

  In the image forming means [K], around the drum-shaped photoconductor 1k as the first image carrier, the charging roller 4k, the developing device 9k using black toner, the transfer roller 11d, the cleaning are arranged in the order of the rotation directions indicated by the arrows. A device 2k is arranged. The transfer roller 11k is rotatable and is in contact with the photoreceptor 1k via the intermediate transfer member 10. The transfer roller 11k is urged toward the photosensitive member 1k by the elastic means 27k. The blade 3k provided in the cleaning device 2k contacts the photosensitive member 1k from the counter direction and scrapes off the transfer residual toner. On the circumferential surface of the photosensitive member 1k, the position between the charging roller 4k and the developing device 9k is a portion to which the exposure light 5k from the exposure device is irradiated. An image is formed.

The image forming means [C], [M], and [Y] are the same as those in the image forming means [K] except that the color of the image to be formed is different. The members having the same functions as in FIG. In addition, subscripts are added as necessary to make identification possible. Incidentally, with respect to the image forming means [C], each constituent member or the like is indicated by a symbol with a subscript c in place of the subscript k in the image forming means [K]. The subscript m is substituted for the subscript k in the means [BK], and the subscript m is attached to the image forming means [Y] in place of the subscript k in the image forming means [BK].
A transfer bias power source 100 is connected to the transfer roller 11y. The same applies to other transfer rollers.

  A secondary transfer roller 21 is provided so as to face the support roller 12 of the intermediate transfer body 10, and a transfer bias power source 102 is connected thereto. A fixing device 30 for fixing the transfer image on the sheet-like medium is provided downstream of the feeding direction indicated by the arrow of the sheet-like medium conveyed through the opposed portion of the support roller 12 and the secondary transfer roller 21 opposed thereto. Is provided. The fixing device 30 has a configuration in which the pressure roller 30b is pressed against the fixing roller 30a.

  When a start switch (not shown) is pressed, one of the support rollers 12, 13, and 14 is rotationally driven by a drive motor (not shown), the other four support rollers are driven to rotate, and the intermediate transfer member 10 is rotated and conveyed. At the same time, the photoconductors 1k, 1c, 1m, and 1y are rotated by the individual image forming means [K], [C], [M], and [Y], and black, cyan, and magenta are respectively formed on the photoconductors 1. A yellow single color image is formed. As the intermediate transfer member 10 is rotated and conveyed, the single color images are sequentially transferred onto the intermediate transfer member 10 by the transfer rollers 11k, 11c, 11m, and 11y to form a composite color image on the intermediate transfer member 10.

  On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers 26 of the paper feed table 31 is selectively rotated, and a sheet is fed out from one of the paper feed cassettes 25 provided in multiple stages in the paper bank. Are separated one by one into the paper feed path, transported by the transport roller 40, guided to the paper feed path in the copying machine main body, and abutted against the registration roller 45 and stopped.

  Then, the registration roller 45 is rotated in synchronization with the composite color image on the intermediate transfer body 10, and a sheet-like medium is fed between the intermediate transfer body 10 on the support roller 12 and the secondary transfer roller 21. A color image is recorded on the sheet-like medium by being transferred by the transfer roller 21. After the image transfer, the sheet-like medium is conveyed by the secondary transfer roller 21 and the intermediate transfer body 10 and sent to the fixing device 30. After fixing the transferred image by applying heat and pressure by the fixing device 30, The paper is fed onto the paper discharge tray 42 by the discharge roller 32 and stacked.

  On the other hand, the intermediate transfer member 10 after the image transfer is removed by the blade 19a with the residual toner remaining on the intermediate transfer member 10 after the image transfer, in preparation for re-image formation by the tandem image forming apparatus.

[2] Composition and operation of the invention (Part 1)
In this embodiment, a cleaning device 19 used for the intermediate transfer member 10 in the tandem image forming apparatus described in FIG. 1 will be described. The blade 19a is made of urethane.

  Since the toner collected by the blade is mixed with paper dust and other foreign matters, it is generally stored in a collected toner container and discarded when it is full. As for the disposal method, the user replaces the container or the service person collects / exchanges it. Therefore, it is preferable that the replacement cycle is long, and it is desirable to increase the toner filling rate in the container as much as possible.

  When the toner collected by the blade 19a as in this example is stored in the container 19b due to free fall due to gravity, for example, when only the same image is printed, the residual toner always remains at the same position in the rotation axis direction of the support roller 13. Therefore, it is conceivable that the toner collected in the container 19b is also concentrated on only a part and piled up. This is not desirable from the viewpoint of filling rate.

  Therefore, in the present invention, as shown in FIG. 2, the toner collection opening 19b-1 of the container 19b is configured to have a longer opening width L2 in the longitudinal direction than the width L1 in the longitudinal direction of the blade 19a. The container 19b can move in the longitudinal direction (left and right direction in FIG. 2) while maintaining the relationship that the width L1 of the 19a is always located within the range of the opening 19b-1, and the stop position after the movement can be changed by the blade 19a. It was decided to accommodate the falling toner. The width L1 of the blade 19a is adjusted to the longitudinal dimension of the support roller 19 (the width of the intermediate transfer member 10).

  One side of the container 19b in the longitudinal direction (the right side in FIG. 2) is pressed by the elastic member 41, and the bottom of the container 19b and the front and rear sides penetrating the paper surface are guided by guide means (not shown). It is possible to move and slide in the longitudinal direction. However, the support roller 13 (intermediate transfer member 10) and the blade 19a do not move in the longitudinal direction of the container 19b. The movement of the container 19b by the elastic member 41 is blocked by an eccentric cam 42 as driving means that contacts the side of the container 19b on the side opposite to the side where the elastic member 41 is provided.

  By stopping the eccentric cam 42 by a predetermined amount, the container 19b changes its stop position in the longitudinal direction with respect to the support roller 13 (intermediate transfer member 10), the blade 19a and the like. When the residual toner scraped off from the blade 19a is stored at this stop position and a certain amount is loaded, the cam 42 is driven to move the container 19b to change the stop position. In this way, the residual toner is accommodated while changing the stop position. Therefore, the toner removed from the intermediate transfer member 10 does not accumulate only in a part of the container, as compared with the conventional technique that accommodates the fixed position. The filling rate is increased.

  The movement of the container 19b is executed based on the magnitude relationship of the amount of toner dropped by the cleaning member in an area where the opening width L2 of the opening 19b-1 is equally divided in the moving direction. It is preferable to control so that the toner loading amount in the region is the same.

  Based on the above control guidelines, the movement position, timing, etc. of the container 19b are information on the print position of the image formed on each of the plurality of image carriers, information on the number of pixels corresponding to the position of the intermediate transfer member 10, and information on the same toner amount. , Or a combination thereof.

  Based on these pieces of information, the toner input amount at the longitudinal position of the container 19b is calculated and predicted, so that the container is moved so that the toner amount is as uniform as possible in the longitudinal direction of the container. As for the position of the container, the current position and the target movement position may be detected by a sensor (not shown), and the rotation amount of the eccentric cam 42 may be set, or may be managed by the rotation speed of a drive source (not shown).

  In this control, it is desirable to control the stop position of the container so that the information on the toner amount in the container longitudinal direction can be stored in as small a position as possible in the longitudinal direction. This is because the toner can be more uniformly accommodated in the container.

[3] Composition and operation of the invention (part 2)
In addition to the movement of the container 19b described above, in this example, the leveling effect is enhanced by applying vibration to the container 19b.
A member that operates in the image forming apparatus is used as a vibration applying unit, and a vibration is applied to the container 19b in conjunction with the movement of the vibration applying unit, so that the upper surface of the toner contained in the container 19b is made uniform. In this way, since a special drive source for applying vibration is not required, the configuration is simplified, the reduction in space efficiency is reduced, and the filling rate can be further improved.

  In this example, as shown in FIG. 1, the intermediate transfer body 10 is supported by support rollers 12, 13, 14, and 15. Of these support rollers, the support roller 13 is attached to the belt-like intermediate transfer body 10. The support roller 15 is a tension roller that applies a predetermined tension necessary for image formation, and the support roller 15 is configured to switch the movement stop position in the vertical direction depending on whether the color of the final image is color or black and white.

  In the arrangement position of the support roller 15 shown in FIG. 1, the intermediate transfer member 10 is in contact with the photosensitive members 1k, 1c, 1m, and 1y to the same extent. In this state, the toner images from the photoconductors 1k, 1c, 1m, and 1y are transferred under the same conditions, which is suitable for obtaining a full color image.

  As shown in FIG. 3 in an enlarged manner, the support roller 13 is pressed by an extensible spring 50 as an elastic means, and the movement of the support roller 13 due to the pressing of the spring 50 is blocked by the tension of the intermediate transfer body 10. ing. Accordingly, when the support roller 15 is moved upward from the position (in FIG. 1) where the support roller 15 is shown by the solid line in FIG. 2 to the position shown by the two-dot chain line in FIG. 3, the transfer roller 11k is used as a fulcrum. The transfer body 10 is also inclined and displaced together with the support roller 15.

  As a result, the contact state between the photosensitive member 1k and the intermediate transfer member 10 does not change, but the other photosensitive members (1m, 1c, 1y) are separated from the intermediate transfer member 10 and a color image is not transferred. It will be in a suitable state. As the support roller 15 moves, the support roller 13 moves in the arrangement direction of the image forming means [K], [C], [M], and [Y] and stops in order to keep the tension constant. Along with this, the container 19b and the blade 19a also move.

  Therefore, the container 19b is configured such that its position is determined with respect to the tension roller (supporting roller 13) as the vibration applying means, thereby switching from the monochrome image forming mode to the full color image forming mode and from the full color image mode to the monochrome image forming mode. Accordingly, every time the support roller 15 stops moving, the container 19b stops moving, and the accommodation loaded toner T in the container 19b is leveled by the vibration at the time of stopping the movement.

  As another example, although not shown, the belt device including the intermediate transfer member is swung around one end of the bell and the device as a fulcrum without displacing the support roller, and the intermediate transfer member 10 and each photosensitive member. The black and white image forming mode and the full color image forming mode can be switched to each other in the same manner as in the above example with respect to the contact / separation relationship with the body. The same toner leveling effect can be obtained by applying vibration to the container 19b by stopping the movement of the container 19b in conjunction with the contact / separation operation with respect to.

  As another example, the secondary transfer roller 21 as the transfer means in FIG. 1 is brought into contact with the support roller 12 only when paper is passed, and is separated when the paper is not passed, and interlocked with the movement of the secondary transfer roller 21. Thus, for example, by configuring the container 19b to be operated by a link mechanism, it is possible to provide the same toner leveling effect by applying vibration to the container 19b. In this case, the secondary transfer roller 21 serves as a vibration applying unit.

  As described above in each example, it is possible to apply vibration to the container 19b by positioning it to a component that always moves at a certain timing, so that the toner in the container is leveled and the filling rate is further improved. The means for applying the vibration is not limited to the above-described example, and it is only necessary to transmit the motion to the container 19b via a link mechanism (not shown) from a drive source that operates periodically and has a relatively large operating force. Since it is not necessary, it is advantageous in terms of cost and space. In the above example, the primary transfer contact / separation of the intermediate transfer body 10 (switching between the monochrome image formation mode and the full color image formation mode) is synchronized with the secondary transfer contact / separation drive (in conjunction with the movement of the secondary transfer roller 21). Since these operations inherently have a large power and a relatively large sound during operation, the vibration sound of the member acting on the container 19b hitting the container 19b does not become annoying.

  The examples of the configuration, operation (part 1), configuration of the invention, and operation (part 2) described above can be executed in combination as appropriate, and a synergistic effect is obtained.

1 is a schematic configuration diagram of an image forming apparatus employing an embodiment of the present invention. FIG. 4 is a partial cross-sectional view of an intermediate transfer body cleaning device. 1 is a diagram illustrating a main part of the present invention in an image forming apparatus.

Explanation of symbols

1 Main body 1k, 1c, 1m, 1y Photoconductor 2k, 2c, 2m, 2y Cleaning device 3k, 3c, 3m, 3y Blade 4k, 4c, 4m, 4y Charging roller 5k, 5c, 5m, 5y (exposure) light 9k, 9c, 9m, 9y Developing device 10 Intermediate transfer member 11k, 11c, 11m, 11y Transfer roller 12, 13, 14, 15 Support roller 19 Intermediate transfer member cleaning device 19a Blade 19b Container 19b-1 Opening portion 21 Secondary transfer roller 25 Feed cassette 26 Feed roller 27 Elastic means 29 Feed roller 30 Fixing device 30a Fixing roller 30b Pressure roller 31 Feed table 32 Discharge roller 40 Transport roller 41 Elastic member 42 Eccentric cam 45 Registration roller 50 Spring 102 Transfer bias power supply L1 Width L2 Opening width T Toner
[K], [C], [M], [Y] Image forming means

Claims (12)

  A second image carrier having an endless belt shape that superimposes toner on a plurality of first image carriers, a cleaning member for removing residual toner on the second image carrier, and the cleaning member A container for storing toner by dropping it directly by gravity, wherein the opening for collecting toner in the container is longer in the longitudinal direction than the longitudinal width of the cleaning member, and the longitudinal width of the cleaning member is An image forming apparatus, wherein the container is movable in the longitudinal direction while always maintaining the relationship of being positioned within the range of the opening, and the fallen toner is accommodated by changing a stop position after the movement.   The image forming apparatus according to claim 1, wherein the container is moved based on image print position information.   The image forming apparatus according to claim 1, wherein the container is moved based on pixel number information of an image formed on each of the plurality of image carriers.   The image forming apparatus according to claim 1, wherein the container is moved based on information on a toner amount on the second image carrier.   The image forming apparatus according to claim 1, wherein at least two or more of image print position information, information on the number of pixels of an image formed on each of the plurality of image carriers, and information on a toner amount on the second image carrier. An image forming apparatus that is executed based on the combined information.   6. The image forming apparatus according to claim 1, wherein the container is moved in accordance with a movement amount of the toner removed by the cleaning member in a region where the opening is divided into a plurality of portions at least equally. An image forming apparatus that is executed based on a magnitude relationship. The image forming apparatus according to claim 1,
A member that operates in the image forming apparatus is a vibration applying unit, and the upper surface of the toner contained in the container is made uniform by applying vibration to the container in conjunction with the movement of the vibration applying unit. Forming equipment.   8. The image forming apparatus according to claim 7, wherein the second image carrier is supported by at least two support rollers, the support rollers include tension rollers, and the container is the tension as the vibration applying unit. An image forming apparatus characterized in that a position is determined with respect to a roller.   8. The image forming apparatus according to claim 7, wherein a belt device including the second image carrier can be brought into contact with and separated from the first image carrier, and the belt device serving as the vibration applying unit. An image forming apparatus, wherein vibration is applied to the container in conjunction with a contact / separation operation. The image forming apparatus according to claim 7, further comprising a transfer unit that transfers a toner image from the second image carrier to a sheet-like medium, and the transfer unit is in contact with the second image carrier. Can be separated,
An image forming apparatus, wherein vibration is applied to the container in conjunction with the contact / separation operation of the transfer unit as the vibration applying unit. In the image forming apparatus that imparts vibration to the container in conjunction with the movement of a member that operates in the image forming apparatus and makes the upper surface of the toner contained in the container uniform.
11. An image forming apparatus comprising a combination of at least two vibration applying units according to claim 8 to make the upper surface of the toner in the container uniform.   An image forming apparatus comprising any combination of claims 1 to 6 and claims 7 to 11.

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