JP3935760B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a full-color image forming apparatus such as a printer, a copying machine, a facsimile, and the like.
[0002]
[Prior art]
In a conventional image forming apparatus, toner remaining on a photoconductor as an image carrier after transfer is removed by a cleaning device, but the removed toner is returned to a developing device and reused without being disposed as waste toner. Toner recycling is employed in various devices. In order to realize such toner recycling, it is necessary to provide a collected toner conveying means for conveying the toner collected by the cleaning device to the developing device. In general, as a method for conveying powder toner, known methods include falling by its own weight, conveyance by screw rotation, conveyance by a conveyor belt, conveyance on an air flow of an air pump, conveyance by a powder pump, and the like.
[0003]
However, in the above-described toner transport system, dropping by its own weight, transport by screw rotation, and transport by a conveyor belt are limited by the arrangement on the discharge side and the reception side. Further, in the conveyance by screw rotation, the toner is easily stressed during the conveyance due to the conveyance distance and the like, and there is a possibility that the image quality is deteriorated more significantly by the recycled toner.
[0004]
In addition, when transported in an air flow of an air pump or transported by a powder pump, the recycled toner is not easily subjected to the stress described above. It must be used to take measures to prevent an increase in internal pressure due to air bleeding. In addition, since the filter is clogged due to use over time, maintenance is also required, resulting in increased running costs. In addition, it is possible to configure the air circulation as a closed path and not use a filter, but since the circulation path includes a cleaning device or the like, it is almost impossible to maintain airtightness. However, the apparatus is large and the cost increases.
[0005]
Furthermore, when the discharge pump is used for the conveyance by the powder pump, air is required for the toner conveyance and thus has the same problem as the above air flow. In addition, when a suction type pump is used, in order to generate a large toner conveying force, the pump becomes larger and the torque increases. To avoid this, the collected toner is sufficiently dispersed on the upstream side of the pump to flow. It is necessary to make it.
[0006]
  As described above, in order to perform toner recycling, there is a big problem in conveying the collected toner. Moreover, the toner collected by the cleaning device has difficulty in charging characteristics, sonormalThe toner that has not been transferred to the toner has a high content, and even normal toner has undergone development, transfer, and cleaning processes. May have deteriorated. For this reason, when the toner is recycled, if the ratio of the recycled toner to the new toner is high, the possibility of image deterioration is extremely high. Therefore, when performing toner recycling, it is necessary to consider reducing the deterioration of image quality due to the use of recycled toner by thoroughly stirring and dispersing the recycled toner with new toner. There wasn't.
[0007]
[Problems to be solved by the invention]
However, in many image forming apparatuses that perform toner recycling, the toner collected by the cleaning device is returned directly to the developing device, and it is insufficient to disperse the toner in new toner and sufficiently agitate it. In particular, in recent years, the amount of the developer stored in the developing device has been reduced due to the compactness of the device, and there is a high possibility that the collected toner conveyed to the developing device will be used without sufficient stirring or the like. .
[0008]
In view of the above-described conventional problems, the present invention provides an image forming apparatus that can recycle toner collected by a cleaning device with a simple configuration and that can significantly reduce deterioration in image quality due to recycled toner. It is intended to provide.
[0009]
[Means for Solving the Problems]
  To achieve the above object, the present invention provides a developing device for processing a visible image of an electrostatic latent image formed on an image carrier, and a cleaning device for cleaning residual toner after the image forming processing of a visible image. And a collected toner processing device for processing the toner collected by the cleaning device, and a toner replenishing device for replenishing the toner to the developing device, wherein the toner replenishing device contains a toner storage container containing the toner and the toner In the image forming apparatus comprising an air supply means for supplying air into the storage container,
  The collected toner processing device includes a recycling device that feeds the collected toner as recycled toner onto air supplied by an air supply unit of the toner replenishing device to the toner storage container.The toner replenishing device is provided with a screw pump including an elastic stator having a spiral groove inside and a rotor that moves the toner in the axial direction by rotating inside the stator. The toner in the toner container is conveyed to the developing device by the negative pressure generated.With featuresAn image forming apparatus is proposed.
[0010]
The present invention is effective when an air filter for adjusting the internal pressure of the toner container is provided.
Furthermore, the present invention is effective when the toner storage container is a replaceable container that can be attached to and detached from the image forming apparatus main body.
[0011]
  Furthermore, the present invention is effective when the toner container is made of a material or shape that can be deformed with respect to fluctuations in internal pressure.
[0012]
Furthermore, the present invention provides a waste toner device having a waste toner storage container for storing the recovered toner as waste toner and a means for transporting the recovered toner to the waste toner storage container, and the cleaning device. It is effective to have switching means for switching the destination of the collected toner to either the recycling device or the waste toner device.
[0013]
Furthermore, the present invention is effective when the collected toner processing apparatus includes a control unit that switches and controls the destination of the collected toner by the switching unit according to the remaining amount of toner in the toner storage container.
[0014]
Furthermore, the present invention is effective when the collected toner processing apparatus includes a control unit that switches and controls the destination of the collected toner by the switching unit according to the state of the collected toner.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic view showing a color copying machine as an example of a color image forming apparatus according to the present invention. In this color copying machine, a copying machine main body 100 is arranged at the center, and a sheet feeding unit 200 configured in a table shape is arranged below the copying machine main body 100. A scanner 300 is disposed above the copying machine main body 100, and an automatic document feeder 400 is disposed above the scanner 300. It is the composition which arranged.
[0016]
The copying machine main body 100 is provided with an intermediate transfer belt 10 as an image carrier constituted by a flexible endless belt wound around a plurality of rollers 14, 15, 16. In the intermediate transfer belt 7, one of the plurality of rollers 14, 15, 16 is rotationally driven by a driving device (not shown), whereby the intermediate transfer belt 10 is driven to run in the clockwise direction indicated by the arrow, and the other The roller rotates. Black, cyan, magenta, and yellow image forming units 18 are arranged side by side on the upper traveling side of the intermediate transfer belt 10 that travels in this way. That is, the tandem image forming apparatus 20 is configured by arranging four image forming units 18 on the running side between the rollers 14 and 15.
[0017]
The four image forming units 18 include a photosensitive drum 40 as a latent image carrier in contact with the intermediate transfer belt 10. Around the photosensitive drum 40, a charging device, a developing device, a cleaning device, a static eliminator, and the like are disposed. Further, a transfer device is disposed inside the intermediate transfer belt 10 at a position where the photosensitive drum 40 contacts the intermediate transfer belt 10. 62 is provided. In the present embodiment, the four image forming units 18 have the same structure, but the toner color of the developing device is divided into four colors of yellow, magenta, cyan, and black. Further, an exposure device 21 for irradiating the surface of each photosensitive drum with light-modulated laser light is disposed above each image forming unit 18, and this laser light is applied to the photosensitive drum between the charging device and the developing device. To do. Although the exposure device 21 may be provided for each image forming unit 18, using the common exposure device 15 is advantageous in terms of cost.
[0018]
On the other hand, a secondary transfer device 22 is provided on the opposite side of the intermediate transfer belt 10 from the tandem image forming device 20. The secondary transfer device 22 is arranged so that a secondary transfer belt 24, which is an endless belt, is wound between rollers 23, and the belt is pressed against the roller 16 via the intermediate transfer belt 10. In FIG. 1, a fixing device 25 for fixing a transfer image carried on the sheet is provided on the left side of the secondary transfer device 22.
[0019]
The secondary transfer device 22 described above is also provided with a sheet transport function for transporting the image-transferred sheet to the fixing device 25. Of course, a non-contact charger may be disposed as the secondary transfer device 22. In such a case, it is necessary to separately provide a sheet conveying device for conveying the transferred sheet to the fixing device 25.
[0020]
In the illustrated example, a sheet reversing device 28 for reversing the sheet so as to record images on both sides of the sheet is provided below the secondary transfer device 22 and the fixing device 25 in parallel with the tandem image forming device 20 described above. It has.
[0021]
Now, when making a copy using a color copying machine having such a configuration, a document is set on the document table 30 of the automatic document feeder 400. Alternatively, the automatic document feeder 400 is opened, a document is set on the contact glass 32 of the scanner 300, and the automatic document feeder 400 is closed and pressed by it.
[0022]
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the other contact glass 32. When this happens, the scanner 300 is immediately driven to travel on the first traveling body 33 and the second traveling body 34. Then, the first traveling body 33 emits light from the light source and further reflects the reflected light from the document surface toward the second traveling body 34, and is reflected by the mirror of the second traveling body 34 and passes through the imaging lens 35. The document is placed in the reading sensor 36 and the original content is read.
[0023]
Further, when a start switch (not shown) is pressed, the intermediate transfer belt 10 is rotated, and at the same time, the photoconductors 40 are rotated by the individual image forming units 18 so that the black, yellow, A magenta / cyan monochrome image is formed. Then, as the intermediate transfer belt 10 travels, the monochrome images are sequentially transferred to form a composite color image on the intermediate transfer belt 10.
[0024]
On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers 42 of the paper feed unit 200 is selectively rotated, and the sheet is fed out from one of the paper feed cassettes 44 provided in multiple stages in the paper bank 43, and the separation roller The sheet is separated one by one at 45 and put into the sheet feeding path 46, conveyed by the conveying roller 47, guided to the sheet feeding path 48 in the copying machine main body 100, abutted against the registration roller 49 and stopped.
[0025]
Alternatively, when manual feeding is selected, the sheet feeding roller 50 is rotated to feed out the sheets on the manual tray 51, separated one by one by the separation roller 52, and put into the manual feeding path 53. Stop by hitting.
[0026]
Then, the registration roller 49 is rotated in synchronization with the composite color image on the intermediate transfer belt 10, the sheet is fed between the intermediate transfer belt 10 and the secondary transfer device 22, and transferred by the secondary transfer device 22. Full color images are recorded on the sheet at once.
[0027]
The image-transferred sheet is conveyed by the secondary transfer device 22 and sent to the fixing device 25. The fixing device 25 applies heat and pressure to fix the transferred image, and then the switching sheet 55 is switched and discharged. The paper is discharged by a roller 56 and stacked on a paper discharge tray 57. Alternatively, it is switched by the switching claw 55 and put into the sheet reversing device 27, where it is reversed and guided again to the transfer position, and an image is recorded also on the back surface, and then discharged onto the discharge tray 57 by the discharge roller 56.
[0028]
On the other hand, the intermediate transfer belt 10 after image transfer is removed by the intermediate transfer body cleaning device 17 to remove residual toner remaining on the intermediate transfer belt 10 after image transfer, and is prepared for re-image formation by the tandem image forming apparatus 20.
[0029]
FIG. 2 is a main part configuration diagram of the copying machine main body in the image forming apparatus according to the embodiment of the present invention. FIG. 3 is an enlarged main part view of the tandem image forming mechanism shown in FIG.
As shown in FIG. 2, four image forming units 18Y, 18M, 18C, and 18Bk are provided in order from the upstream side of the intermediate transfer member 10. As shown in FIGS. 2 and 3, each image forming unit 18 (18Y, 18M, 18C, 18Bk, and the like) has a charging device 60, an optical writing system L, developing devices 61, 1 around the photosensitive member 40. A next transfer device 62, a cleaning device 63, and a charge removal device 64 are provided. With this arrangement, it is possible to shorten the first copy time in the Bk single color mode by the conveyance distance between the most upstream photoreceptor 40Y and the most downstream photoreceptor 40Bk. Further, since the image forming unit 18Bk is located away from the fixing device 25 that is a heat generation source, a large-capacity toner tank (not shown) can be provided for the image forming unit 18Bk that is frequently used. Increased freedom.
[0030]
FIG. 4 is an internal configuration diagram of the image forming unit according to the embodiment of the present invention.
The cleaning device 63 is provided with a recovery screw 79 that conveys the recovered toner in a direction parallel to the axis of the photoreceptor 40, and the recovery screw 79 is driven via a coupling 93 from a main body side cleaning drive shaft (not shown). It is transmitted and driven to rotate. Here, the rotation direction of the cleaning drive shaft can be controlled forward and backward by a stepping motor (not shown), and the toner in the cleaning device 63 is moved to the front side or the back side depending on the rotation direction of the recovery screw 79. The discharge direction can be selected in the direction of the side end.
[0031]
The image forming apparatus according to the present exemplary embodiment is provided with a collected toner processing apparatus that includes a recycling apparatus 80 that processes toner collected by the cleaning apparatus 63 and a waste toner apparatus 90. When the recovered toner 79 is conveyed forward by the normal rotation of the recovery screw 79, the recovered toner processing apparatus finally supplies the recovered toner as recycled toner to the developing device 61 by the recycle device 80 communicating with the front end of the screw. Be transported. On the other hand, when the toner is conveyed in the back direction by the reverse rotation of the collecting screw 79, the collected toner is conveyed as waste toner to a waste toner tank (not shown) by the waste toner device 90 and stored. As shown in FIG. 3, the cleaning device 63 of the present embodiment includes a fur brush 76. The fur brush 76 is assumed to rotate in a fixed direction regardless of the screw driving direction. It is driven by connection.
[0032]
FIG. 5 is a recovery screw drive control block diagram.
The collection screw 79 is configured such that the rotation direction of the drive motor 102 is switched by the rotation direction switching control means 101. By switching the drive motor 102, the collection screw 79 is rotated forward and backward to recycle the collected toner into the recycling device 80 or waste. The toner is switched to the toner device 90 and collected.
[0033]
FIG. 6 is a configuration diagram of a toner supply mechanism for supplying toner to the developing device 61 of the image forming unit 18.
In FIG. 6, a toner storage container 180 storing toner to be replenished to the developing device 61 is set in a set unit (not shown) provided in the copying machine main body 100. A nozzle 190 to be inserted into the toner storage container 180 is erected in the set portion, and the nozzle 190 is inserted by setting the toner storage container 180 from above to the set portion. The nozzle 190 has a single tube structure, and a tip member 191 formed in a conical section in the upper part is provided by integral molding or fixing, etc., and an air supply port and a toner supply port are provided following the tip member 191. An opening 192 is also provided. The opening 192 communicates with the passage 193, and the passage 193 is provided with a toner connection port 194 to which the toner transport tube 159 is connected. The passage 193 is provided with an air connection port 195 above the toner connection port 194.
[0034]
In the case of this embodiment, the air connection port 195 is connected to an air pump 196 as air supply means via an air conveyance pipe 197. When the air pump 196 is activated, air is ejected from the lower side into the toner container 180 through the air transport pipe 197 and the passage 193. Then, the air blown into the toner storage container 180 passes through the toner layer and fluidizes the toner while stirring. A valve 198 is provided in the middle of the air conveying pipe 197, and serves to keep the air passage closed when a powder pump described later is operated.
[0035]
The toner storage container 180 is configured as a back-in-box type having an outer box 181 as a protective case and a toner bag 182 as a flexible and deformable bag-like body detachably accommodated in the outer box 181. ing. The outer box 181 is made of a material such as paper, cardboard, or resin having rigidity, and has an internal space that can accommodate the toner bag 182. Even if the toner bag 182 containing the toner is flexible, the toner storage container 180 is protected against an impact from the outside by being stored in the outer box 181, and the handling property is improved. The advantage is that it is easy to perform and easy to organize during storage.
[0036]
  In addition, the bag portion of the toner bag 182 has a single-layer or multi-layer structure made of a flexible sheet material (a thickness of about 80 to 125 μm) such as a polyester film or a polyethylene film.Container shaped bagIt is. And toner bag182The toner is provided with a toner discharge hole at the lower center, and a base member 183 made of a resin such as polyethylene or nylon is fixed. The toner discharge hole of the base member 183 is provided with a single-layer or multi-layer seal 184 that functions as a self-closing valve, and the seal 184 is made of an elastic body made of a non-breathable foamed sponge or the like. Further, the toner bag 182 is formed in a shape that tapers toward the toner discharge hole so that the toner hardly remains. Therefore, when the toner container 180 configured as described above is set in the setting unit, the nozzle 190 is inserted from the lower side in the vertical direction, that is, from directly below. In addition, the toner bag182Is provided with a filter 185 as an internal pressure adjusting means that allows air to pass therethrough but prevents toner from passing therethrough. The toner storage container 180 may be provided with a mechanical shutter that automatically closes the toner discharge port by a spring force when the container is taken out.
[0037]
On the other hand, the developing device 61 is provided with a sub hopper 161 at the upper portion thereof, and the toner in the toner storage container 180 is once stored in the sub hopper 161 and then supplied to the developing device 61. A powder pump 170 is provided on the sub hopper 161 as means for conveying the toner in the toner container 180 to the sub hopper 161. This powder pump 170 is a uniaxial eccentric screw pump, and is made of a rotor 171 made of a screw shape eccentric with a material having rigidity such as metal, and an elastic body such as rubber, and is a double screw shape. And a holder 173 made of a resin material or the like that wraps these and forms a powder conveyance path. In the rotor 171, a gear (not shown) integrally connected to a drive shaft 174 connected by a pin joint is drivingly connected to a clutch via an idle gear (not shown). The operation of the body pump 170 is controlled.
[0038]
Further, a toner suction portion 177 is provided at the tip of the holder 173, that is, the right end in FIG. 6, and the toner transport tube 159 is connected to the toner suction portion 177. As the toner conveying tube 159, for example, a flexible tube having a diameter of 4 to 10 mm and made of a rubber material having excellent toner resistance (for example, polyurethane, nitrile, EPDM, silicon, etc.) is extremely used. An effective and flexible tube can be easily piped up and down, left and right. If the powder pump 170 described above is used, the toner in the toner storage container 180 can be smoothly transported even when the toner discharge port of the toner storage means is at a lower position in the vertical direction than the toner receiving port of the sub hopper 161. Can do. The detailed description of the subpopper 161 is not the gist of the present invention, and will be omitted.
[0039]
Next, the above-described recycling apparatus 80 will be described with reference to FIG.
In FIG. 7, a joint (not shown) is provided at the front end of the cleaning device 63, and one end of a recycled toner transport tube 110 serving as a recycled transport path is connected to the joint. The other end of the recycled toner transport tube 110 is connected to the suction port 196a of the air pump 196 described above. Therefore, the recycled toner conveyed forward by the forward rotation of the recovery screw 79 is conveyed to the toner storage container 180 on the air supplied from the supply port 196b of the air pump 196 using the suction force of the air pump 196. . The recycled toner conveyed to the toner container 180 is mixed with new toner here, and is sent to the developing device 61 by the powder pump 170 for use.
[0040]
Thus, in the image forming apparatus of the present embodiment, the recycled toner is transported to the toner storage container 180 using the air pump of the existing toner replenishing device, where it is mixed with new toner and finally transported to the developing device 61. The toner can be recycled without providing a dedicated toner conveying means.
[0041]
By the way, when the toner is transported by an air flow, there is a risk that the toner may be ejected due to an increase in internal pressure at the transport destination, but the toner storage container 180 is provided with an air filter 185 above the toner bag 182. Therefore, the increase in internal pressure can be suppressed. In addition, since the toner bag 182 is made of a flexible material, even if the internal pressure of the toner storage container 180 suddenly rises immediately after air supply, the container swells and the internal pressure rises abnormally. Is prevented. Therefore, the air supply to the toner container 180 not only stirs and fluidizes the stored toner but also moves the wall surface of the toner bag 182, thereby suppressing the occurrence of toner crosslinking and the like.
[0042]
Next, the waste toner device 90 will be described.
As shown in FIG. 3, the waste toner device 90 is provided with a joint (not shown) at the rear end portion of the cleaning device 63, and a waste toner vertical passage 91 is connected to the joint. The waste toner vertical passage 91 is connected to a common passage 92 extending in the horizontal direction. A conveying screw 92a is built in the common passage 92, and waste toner dropped into the common passage 92 by driving the screw 92a is sent to a waste toner tank (not shown) and stored therein. The waste toner device 90 is provided with a considerably long conveying screw 92a. If the toner is conveyed with such a screw, there is a risk of stressing the toner. there is no problem.
[0043]
Next, an example of controlling whether the toner collected by the cleaning device 63 is recycled or used as waste toner will be described.
It is inevitable that using recycled toner is inferior in image quality as compared with using only new toner. Therefore, in the control example of this example, whether to use recycled toner or waste toner is determined depending on whether or not degradation of image quality can be suppressed by using the recycled toner. In other words, if the image quality is hardly degraded or not noticed, recycling is effective both economically and environmentally, and if the image quality clearly falls, it is discarded without recycling.
[0044]
When the processing of the collected toner is selected from such a viewpoint, first, the ratio of the collected toner and the recycled toner becomes a problem. Accordingly, whether or not the collected toner is to be recycled is determined based on the remaining amount of toner in the toner container 180. That is, when the remaining amount of toner in the toner storage container 180 becomes a predetermined value or less, the toner is supplied to the developing device by forcibly switching to the waste toner transport mode and stopping the supply of the collected toner to the toner storage container 180. It is possible to control the percentage of recycled toner mixed in the toner to be less than the predetermined value, and to reduce the influence on image quality deterioration such as image scumming due to the influence of the charging characteristic deteriorated toner mixed in the recycled toner. Is possible.
[0045]
Such control requires means for detecting the remaining amount of toner in the toner storage container 180. Examples of the detection means include direct detection using a piezoelectric or optical sensor, and toner discharge means for the toner storage container 180. A method such as indirect detection based on an integrated driving time value (for example, in the present embodiment, the driving time of the driving clutch of the powder pump 170) is conceivable. In the present embodiment, a piezoelectric sensor (not shown) is installed in the sub hopper 161, and the toner output is detected when the sensor output does not generate the toner full detection output when the powder pump 170 is driven for a predetermined time. A method of detecting that the amount of toner in the storage container 170 is equal to or less than a predetermined value is used. In this configuration, even when the toner end in the toner storage container 170 is detected, a predetermined amount of toner is secured in the sub hopper 161, and the supply of recycled toner to the toner storage container 180 is stopped. In this case, mixing of recycled toner does not fall below a predetermined ratio.
[0046]
However, since there may be different image quality requirements (acceptability for image quality degradation) for each user who uses the machine, the above-mentioned toner-end-recovered toner supply stoppage is performed assuming a user who prioritizes toner yield. This control can also be configured to be selectable (can be set).
[0047]
It is also effective to switch the control of whether the toner collected by the cleaning device 63 is recycled or waste toner according to the image forming mode. That is, in the color image formation mode in which the toner discharged from the cleaning device 63 may be mixed with other color toners, the collected toner is routed to the waste toner conveyance path, and in the single color image formation mode, the control is sent to the recycle path. It is.
[0048]
Furthermore, it is also effective to switch the control of whether the toner collected by the cleaning device 63 is recycled or waste toner based on the output result of the image detection sensor. That is, for example, a background stain on the non-image area is detected by the optical sensor on the photosensitive member or the intermediate transfer belt, and when the background dirt is generated on the non-image area, the collected toner is routed to the waste toner conveyance path. It is.
[0049]
Furthermore, it is also effective to switch the control of whether the toner collected by the cleaning device 63 is recycled or waste toner based on the output result of the environment detection sensor. That is, for example, the temperature and humidity sensor detects the inside of the machine and the surrounding environment, and when an abnormal image is generated due to a difference in charging characteristics between new toner and recycled toner at low temperature and low humidity, the recovered toner is routed to the waste toner conveyance path.
[0050]
Furthermore, it is also effective to control whether the toner collected by the cleaning device 63 is recycled or used as waste toner by switching immediately after the start of image formation based on the machine stop time. That is, when the leaving time after the machine is stopped is long, the collected toner remaining in the cleaning device 63 absorbs moisture due to the surrounding environment. When the charging characteristics change due to moisture absorption, the residual toner is not conveyed to the toner storage container 180 immediately after the image formation is resumed. In the meantime, the control is switched to the waste toner conveyance path.
[0051]
As described above, the toner collected by the cleaning device 63 is controlled by a control unit (not shown) according to the remaining amount of toner in the toner container 180 or the state of the collected toner.
[0052]
【The invention's effect】
  According to the configuration of the first aspect of the present invention, the collected toner processing device includes the recycling device that carries the collected toner as recycled toner on the air supplied by the air supply unit of the toner replenishing device and sends it to the toner storage container. The toner can be recycled by skillfully using the. Therefore, a special device for toner recycling is unnecessary and can be provided at low cost. Furthermore, since the recycled toner is sent to the toner storage container, it is sufficiently mixed with stirring with the new toner, and deterioration of image quality can be suppressed as much as possible. Further, in the first aspect, since the toner in the toner storage container is conveyed to the developing device by the negative pressure generated by the screw pump, the air tightness on the toner discharge port side is improved with respect to the air supplied to the toner storage container. In addition to preventing toner scattering in the sub-tank and developing unit of the toner replenishment destination, the recycled toner injected into the toner storage container on the air directly enters the toner replenishment path before being dispersed in the toner cerebellar container. Can be prevented from flowing in.
[0053]
According to the second aspect of the present invention, since the air filter for adjusting the internal pressure of the toner storage container is provided, even if the recovered toner is conveyed by air, the increase in the internal pressure in the toner storage container as the destination can be suppressed, Toner leakage and scattering due to an increase in internal pressure can be prevented.
[0054]
According to the configuration of the third aspect, since the toner storage container is a replaceable container that can be detachably attached to the main body of the image forming apparatus, the toner storage container is replaced together with the air filter when the toner ends. The air filter can be maintained without clogging without maintenance.
[0055]
According to the fourth aspect of the present invention, since the toner container is made of a material or a shape that can be deformed with respect to fluctuations in internal pressure, the container can be used even if a sudden increase in internal pressure occurs at the beginning of air injection. The load applied to the filter can be reduced by the change in volume due to the deformation.
[0056]
According to the fifth aspect of the present invention, the toner replenishing device is provided with a screw pump including an elastic stator having a spiral groove therein and a rotor that moves the toner in the axial direction by rotating inside the stator. In addition, since the toner in the toner storage container is conveyed to the developing device by the negative pressure generated by the screw pump, the air tightness on the toner discharge port side can be increased with respect to the air supplied to the toner storage container. In addition to preventing toner scattering in the sub-tank and developing unit to which toner is supplied, recycled toner injected into the toner storage container on the air flows directly into the toner supply path before being dispersed in the toner cerebellar container. Can be prevented.
[0057]
  Claim5According to the configuration, the collected toner processing device is collected by the cleaning device and the waste toner storage container having the waste toner storage container for storing the recovered toner as waste toner and the means for transporting the recovery toner to the waste toner storage container. Since there is a switching means for switching the toner destination to either the recycling device or the waste toner device, it is possible to minimize degradation of image quality due to toner recycling.
[0058]
  Claim6With this configuration, since the collected toner processing apparatus includes the control unit that switches and controls the destination of the collected toner by the switching unit according to the remaining amount of toner in the toner storage container, the mixing ratio of the recycled toner to the new toner is high. The influence on the image quality due to becoming too much can be suppressed.
[0059]
  Claim7With this configuration, the collected toner processing apparatus includes a control unit that switches and controls the destination of the collected toner by the switching unit according to the state of the collected toner. Therefore, image quality due to poor charging of the toner, change in fluidity, and the like. The influence on can be suppressed.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing a color copying machine as an image forming apparatus according to the present invention.
FIG. 2 is a main part configuration diagram of the copying machine main body of FIG. 1;
FIG. 3 is an enlarged view of a main part of the tandem image forming mechanism shown in FIG.
FIG. 4 is a perspective view showing an internal configuration of a Bk image forming unit of the present invention.
FIG. 5 is a recovery screw drive control block diagram.
FIG. 6 is a configuration diagram of a toner replenishing device used in the image forming apparatus according to the present invention.
FIG. 7 is an explanatory diagram of a configuration of a recycling apparatus for an image forming apparatus according to the present invention.
[Explanation of symbols]
18 Image creation unit
20 Tandem image forming mechanism
21 Exposure equipment
40 photoconductor
61 Developer
63 Cleaning device
79 Recovery screw
80 Recycling equipment
90 Waste toner device
100 Copier body
110 Recycled toner transport tube
159 Toner transport tube
170 Powder pump
171 Rotor
172 Stator
180 Toner container
185 Air filter
190 nozzles
196 Air pump
197 Air conveying pipe

Claims (7)

A developing device that performs visible image processing on the electrostatic latent image formed on the image carrier, a cleaning device that cleans residual toner after the image forming processing of the visible image, and toner collected by the cleaning device is processed. A recovery toner processing device and a toner supply device for supplying toner to the developing device, wherein the toner supply device includes a toner storage container storing toner and an air supply means for supplying air into the toner storage container. In the image forming apparatus provided,
The collected toner processing device includes a recycling device that feeds the collected toner as recycled toner onto the air supplied by the air supply means of the toner replenishing device and sends it to the toner storage container. There is provided a screw pump provided with a stator of an elastic member having a spiral groove and a rotor that moves the toner in the axial direction by rotating inside the stator, and the negative pressure generated by the screw pump causes the inside of the toner storage container to An image forming apparatus, wherein toner is conveyed to a developing device.   2. The image forming apparatus according to claim 1, wherein the toner storage container is provided with an air filter for adjusting an internal pressure thereof.   3. The image forming apparatus according to claim 2, wherein the toner storage container is a replaceable container that can be detachably attached to the main body of the image forming apparatus.   4. The image forming apparatus according to claim 2, wherein the toner storage container is made of a material or a shape that can be deformed with respect to fluctuations in internal pressure.   2. The waste toner device according to claim 1, wherein the collected toner processing device includes a waste toner storage container that stores the collected toner as waste toner, and a unit that transports the collected toner to the waste toner storage container; An image forming apparatus comprising: a switching unit that switches a destination of the toner collected by the cleaning device between the recycling device and the waste toner device.   6. The image forming apparatus according to claim 5, wherein the collected toner processing device includes a control unit that switches and controls a destination of the collected toner by the switching unit according to a remaining amount of toner in the toner storage container. Image forming apparatus. 6. The image forming apparatus according to claim 5 , wherein the collected toner processing apparatus includes a control unit that switches and controls a destination of the collected toner by the switching unit according to a state of the collected toner. .

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