JP4770410B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus using an electrophotographic system such as a copying machine or a printer. More specifically, the residual developer on the image bearing member or intermediate transfer member removed by the cleaning device is recovered by a reuse recovery device. The present invention relates to a reusable image forming apparatus.

  Conventionally, in an image forming apparatus using an electrophotographic method, an electrostatic latent image is formed on the surface of an image carrier made of a drum-type photosensitive member or the like, and toner is supplied from the developing device to the surface of the image carrier to electrostatically The latent image is used as a toner image, and the toner image is transferred to a recording medium or an intermediate transfer member.

As such an image forming apparatus, residual toner on the surface of the image carrier after transfer is removed by a cleaning unit, and the removed toner is collected as a recycled toner in a developing device which is a reuse collection device, and is twice or three times. A technique has been developed in which toner that has been used more than once is not collected in the developing device (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 7-104631

  However, in the conventional image forming apparatus, the toner used twice or three times or more is not collected in the developing device. Even if the toner is not a regular product, the first used toner is It will be collected by the developing device.

  However, some non-genuine toners are difficult to determine whether they can be recycled due to the characteristics of the toner, and if such unidentified toner is collected in a developing device and reused, the print image will deteriorate. There was a problem of inviting.

  The present invention has been made to solve such a problem, and when a developer such as toner is not a regular product, it is not reused, and a non-genuine developer is reused. An object of the present invention is to provide an image forming apparatus capable of preventing the occurrence of image deterioration due to the above.

The above problem is solved by the following means.
(1) An image carrier on which an electrostatic latent image is formed on the surface, a developing device for developing the electrostatic latent image on the image carrier as a developed image with a developer , and a recording medium or intermediate transfer of the developed image after transfer to the body, determine a cleaning means for removing the developer remaining adhered to the surface of the image bearing member or an intermediate transfer member surface, the pre-granted information to the developing device, developer whether genuine a developer discriminating means for, wherein when it is determined that genuine by the developer discriminating means, the developer removed by the cleaning means is recovered to the developing device, when it is judged not to be genuine An image forming apparatus comprising: control means for controlling the components of the apparatus so as not to be collected.
(2) An image carrier on which an electrostatic latent image is formed on the surface, a developing device that develops the electrostatic latent image on the image carrier as a developed image with a developer, and a recording medium or intermediate transfer of the developed image Cleaning means for removing developer remaining on the surface of the image carrier or intermediate transfer body after transfer to a body, developer determination means for determining whether or not the developer is a genuine product, and the developer The configuration of the apparatus is configured such that the developer removed by the cleaning unit is collected by the developing device when the judging unit determines that the product is genuine, and is not collected when the developer is determined not to be genuine. and a control means for controlling the elements, wherein the control means controls the developing output voltage of the developing device, the image formation and controls so that the developer can not be recovered in the developing device apparatus.
(3) An image carrier on which an electrostatic latent image is formed on the surface, a developing device for developing the electrostatic latent image on the image carrier as a developed image with a developer, and a recording medium or intermediate transfer of the developed image Cleaning means for removing developer remaining on the surface of the image carrier or intermediate transfer body after transfer to a body, developer determination means for determining whether or not the developer is a genuine product, and the developer The configuration of the apparatus is configured such that the developer removed by the cleaning unit is collected by the developing device when the judging unit determines that the product is genuine, and is not collected when the developer is determined not to be genuine. and a control means for controlling the elements, wherein the control means, by retracting the developing device from a predetermined position, the image forming apparatus characterized by controlling so that the developer can not be recovered in the developing device .
(4) a waste developer tank for accumulating the developer removed by the cleaning means; and a developer returning means for returning the developer accumulated in the developer tank to the developing device; 2. The image forming apparatus according to item 1, wherein control is performed so that the developer is not collected by the developing device by not operating the developer returning means.
(5) when said developer further comprises a monochrome color determining means for determining whether monochrome or color, the developer is determined to be a monochrome developer by the monochrome color determining means, the control means , it said regardless genuine whether determination result by the developer discriminating means, any one of items 1 to 4 in which developer removed by the cleaning means is controlled so as to be recovered to the developing device The image forming apparatus described in 1.
(6) An image carrier on which an electrostatic latent image is formed on the surface, a developing device for developing the electrostatic latent image on the image carrier as a developed image with a developer, and a recording medium or intermediate transfer of the developed image A cleaning means for removing the developer remaining on the surface of the image carrier or the intermediate transfer body after transfer to a body; a removable waste developer container for accumulating the developer removed by the cleaning means; A developer supply container for supplying the developer to the developing device; a developer determining means for determining whether or not the developer is a regular product based on information given in advance to the developer supply container; and the developer determining means The apparatus is configured so that the developer removed by the cleaning unit is collected in the waste developer container when it is determined as a genuine product by the cleaning unit, and is not collected when it is determined as a non-genuine product. Element Comprising a Gosuru control means, wherein the waste developer container, an image forming apparatus wherein the reusable as the developer supply container.

According to the invention of the above (1), the electrostatic latent image is formed on an image carrier, the electrostatic latent image developer is supplied from the developing device is the developing image. After the developed image is transferred onto the recording medium or an intermediate transfer member, the developer remaining adhered to the surface of the image bearing member or an intermediate transfer member surface is removed by a cleaning means.

On the other hand, by the developer discriminating means, the information the developer whether genuine has been previously assigned to the developing device, is determined, if it is determined that genuine has been removed by the cleaning means developing The components of the image forming apparatus are controlled so that the agent is recovered by the developing device and is not recovered when it is determined that the agent is not a regular product.

In other words, the developer is not genuine is not to collect in the developing device, to avoid re-use. Thus, it is possible to prevent the occurrence of image degradation in the case of reusing the recovered developer is not genuine.

By the invention according to the above (2) lever, the control of the developing output voltage of the developing device, it is possible to developer removed by the cleaning means is easily controlled so as not to be recovered to the developing device.

By the invention according to the above (3) lever, by retracting the developing device from a predetermined position, as developer removed by the cleaning unit is not recovered in the developing device, it can be reliably controlled.

According to the invention of the above (5), for monochrome developer for less likely to occur image deterioration even without a legitimate product, regardless of whether the determination result is genuine, is removed by a cleaning means development agent is controlled so as to be recovered into the developing device, it is possible to effectively utilize the developer.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view showing a basic configuration of a printing unit 30 of an image forming apparatus according to an embodiment of the present invention.

  A printing unit 30 of the image forming apparatus includes an image carrier 1, a charging roller 2, an exposure unit 3, a cleaning device 4, a developing device 5, an intermediate transfer member 8, and a bias roller 9 as an example of a transfer device. And a control unit 15 and the like.

  The image carrier 1 is composed of, for example, a drum-shaped photoconductor, and is configured to be rotated in the clockwise direction (arrow a direction) in FIG.

  Around the image carrier 1, the charging roller 2, the exposure unit 3, the developing device 5, and the cleaning device 4 are arranged in this order along the clockwise direction.

  The charging roller 2 as a charging device applies a negative high voltage to uniformly charge the surface of the image carrier 1 to a negative polarity.

  The exposure unit 3 forms an electrostatic latent image corresponding to the original image by forming an original image on the surface of the image carrier 1. An electrostatic latent image corresponding to the document image may be formed by optical writing on the image carrier 1 with a laser beam or the like.

  The developing device 5 is of a dry type, for example, and is provided to face the image carrier 1. The developing device 5 contains a two-component developer containing toner and carrier. These developers are agitated by a stirring roller (not shown) in the developing chamber and are frictionally charged.

  The developing device 5 has a developing roller 6 for supplying the agitated toner to the surface of the image carrier 1. The developer roller 6 is supplied with and supported by the frictionally charged developer to form a magnetic brush made of the developer. The magnetic brush jumps over the air gap of the DS roller 7 and is applied to the surface of the image carrier 1. A DC voltage and an AC voltage are applied to the developing roller 6 so as to jump to the electrostatic latent image.

  Further, the developing device 5 is provided with a memory 12 that stores information related to the developing device 5. Information about whether the developing device 5 is a regular product or an irregular product, in other words, whether the toner is a regular product or an irregular product, is also stored in the memory 12 in advance as information about the development device 5. ing.

  Here, the genuine toner is a genuine toner, a compatible toner, or a toner that satisfies at least one of the conditions that satisfy a conformity condition that ensures a certain quality.

  The intermediate transfer member 8 is an endless belt that is moved toward and away from the image carrier 1 by the movement of a push-up lever (not shown), and is rotated by a feed roller 11. In the transfer portion between the developing device 5 and the cleaning device 4, the toner image on the image carrier 1 is transferred to the recording medium S that is conveyed while being held by the intermediate transfer member 8 in the case of the primary transfer method. In the case of the secondary transfer method, the image is transferred to the intermediate transfer body 8. In the case of the secondary transfer method, the toner image transferred to the intermediate transfer body 8 is transferred to the recording medium S by the secondary transfer roller 10.

  The bias roller 9 presses the intermediate transfer member 8 against the surface of the image carrier 1 at the transfer portion. When a voltage of about −1.5 to −2 kV is applied to the bias roller 9, the image carrier is supported. The toner image on the surface of the body 1 is transferred to the recording medium S held on the intermediate transfer body 8 or the intermediate transfer body 8.

  The cleaning device 4 is provided at a position opposite to the developing device 5 at a position facing the surface of the image carrier 1. The cleaning device 4 is composed of a charging brush which is an example of a cleaning member, and scrapes off and removes toner remaining on the surface of the image carrier 1 after transfer.

  In the case of the secondary transfer system, the residual toner on the intermediate transfer body 8 is scraped off by the cleaning blade 13 and collected in the waste toner bottle 14.

  The control unit 15 includes a CPU, and performs overall control of the entire image forming apparatus including the print unit 30. In addition, the control unit 15 uses information written in the memory 12 of the developing device 5 as a toner type detection unit 27 (FIG. 2). And a function of determining whether the developing device 5 (toner) is a genuine product. Then, when it is determined that the developing device 5 (toner) is a regular product, the residual toner removed by the cleaning device 4 is controlled to be collected by the developing device 5 as a reuse collecting device, When it is determined that the product is not a regular product, control is performed so that the developing device 5 does not collect the product. However, even if the monochrome developing device is not a regular product, control is performed so that the residual toner removed by the cleaning device 4 is collected by the developing device 5. Specific contents of the control will be described later.

  FIG. 2 is a block diagram illustrating an electrical configuration of the image forming apparatus.

  2, this image forming apparatus includes a control unit 15 having a CPU, a ROM 21 and a RAM 22 connected to a bus 20 of the CPU, a network interface (network I / F) unit 23, an operation panel 24, a storage A unit 25, a scanner unit 26, a toner type detection unit 27, a printing unit 30, and the like.

  The ROM 21 is a memory that stores a CPU operation program, and the RAM 22 is a memory that provides a work area when the CPU operates.

  The network I / F unit 23 manages communication and data exchange with user terminals on the network.

  The operation panel 24 has functions such as an operation unit for performing various settings, and includes a keyboard and a display unit (not shown).

  The storage unit 25 stores various applications and data. In this embodiment, the storage unit 25 includes a model information storage unit 25a in which model information of the developing device 5 suitable for the apparatus is stored.

  The scanner unit 26 reads a document image.

  The toner type detection unit 27 is connected to the memory 12 of the developing device 5 and reads information written in the memory 12.

  The printing unit 30 includes the image carrier 1, the cleaning device 4, the developing device 5, and the intermediate transfer member 8 as described above, and prints image data on the recording medium S.

  Next, the operation of the image forming apparatus shown in FIGS. 1 and 2 will be described with reference to the timing charts of FIGS. In the following description, a primary transfer method in which the toner image on the image carrier 1 is directly transferred to the recording medium S will be described as an example.

  A main motor (not shown) is driven to rotate in response to the turning on of the print signal, and thereafter, feeding of the recording medium S is started by a paper feeding clutch (not shown).

  First, the surface of the image carrier 1 is uniformly charged to a negative polarity, for example, −800 V, by a charging device including a charging roller 2 that applies a negative high voltage. Next, a document image (not shown) is formed and projected onto the surface of the image carrier 1 by the exposure unit 3, so that an electrostatic latent image corresponding to the document image is formed on the surface of the image carrier 1. It is formed.

  The image carrier 1 on which the electrostatic latent image is formed further rotates in the clockwise direction, but the frictionally charged developer is supplied and carried on the developing roller 6 of the developing device 5 disposed opposite to the image carrier 1. As a result, a magnetic brush made of a developer is formed.

  The magnetic brush jumps over the air gap of the DS roller 7 by the voltage applied to the developing roller 6, and jumping development is performed on the electrostatic latent image on the surface of the image carrier 1.

  Then, the electrostatic latent image is developed as a visible toner image by electrostatically transferring the toner to the latent image. In this manner, the electrostatic latent image on the surface of the image carrier 1 is developed as a toner image by the developing device 5.

  Next, the visible toner image on the image carrier 1 is transferred to the recording medium S on the intermediate transfer member 8 as follows. That is, a transfer bias is applied to the bias roller 9 and a charge having a polarity opposite to the polarity of the toner image on the image carrier 1 is applied to the intermediate transfer member 8. Accordingly, the toner image on the surface of the image carrier 1 is transferred onto the recording medium S.

  In this embodiment, the image carrier 1 whose surface is charged to −800 V is developed with a positive toner, and a voltage of −1.5 to −2 kV is applied to the bias roller 9 to carry the image carrier. The toner image on the surface of the body 1 is transferred onto the recording medium S on the intermediate transfer body 8.

  In performing the transfer, the recording medium S is sent onto the intermediate transfer member 8 and electrostatically adsorbed in a state where the timing is adjusted by a registration roller (not shown), and as the intermediate transfer member 8 travels. Pass through the transcription site.

  The recording medium S is separated from the intermediate transfer member 8 by the curvature at the position of the field roller 11 where the intermediate transfer member 8 is passed.

  When a series of transfer operations are completed, a push-up lever (not shown) is released, and the intermediate transfer member 8 is separated from the image carrier 1.

  The recording medium S to which the toner image has been transferred is thermally fixed by a pair of fixing rollers (not shown) and discharged outside the apparatus by a pair of discharge rollers (not shown).

In this embodiment, the control unit 15 reads out information related to the developing device 5 from the memory 12 of the developing device 5 via the toner type detection unit 27, and based on the read information, whether or not the developing device 5 is a genuine product. Is determined. Then, based on the determination result, the following control is performed for the removal and collection of the residual adhered toner on the image carrier 1.
(I) When it is determined that the developing device 5 is a genuine product (FIG. 3).
The cleaning device 4 scatters and removes the scraped toner by applying an AC voltage to the charging brush, and the discharged toner moves to the developing device 5 by the negative potential output of the developing roller 6 and is collected. Is done.

  The operating time of the developing roller 6 is a predetermined time T1 set by the timer of the control unit 15 from the time when the leading edge of the recording medium S passes a timing sensor (not shown). During this time, it rotates while outputting the development voltage.

As shown in FIG. 3, the voltage application to the bias roller 9 is turned off at the time t2 when the transfer is completed. This is because the residual toner on the image carrier 1 is collected by the developing device 5 and therefore need not be collected by the bias roller 9.
(II) When it is determined that the developing device 5 is not a regular product (FIG. 4).
The cleaning device 4 scatters and removes the scraped toner by applying an AC voltage to the charging brush, but by turning off the development output voltage of the developing roller 6 at time t2, the toner developing device 5 To prevent the toner from being collected. The operation time of the developing roller 6 is a predetermined time T2 from the time when the leading edge of the recording medium S passes a timing sensor (not shown) to the time t2.

  As described above, if the toner removed by the cleaning device 4 is not a regular one that can be recycled, the developing device 5 prevents the toner from being collected. Can be prevented.

  The toner that has not been collected is adhered onto the intermediate transfer member 8 by continuing to apply a voltage of −1.5 to −2 kV to the bias roller 9. The adhered toner is scraped off by a cleaning blade 13 provided downstream of the intermediate transfer member 8 and collected in a waste toner bottle 14.

  The operation time of the bias roller 9 is a predetermined time T1 set by the timer of the control unit 15 from the time when the leading edge of the recording medium S passes the timing sensor, and rotates while bias is output for this time T1.

  The recovery process of the residual toner of the image carrier 1 to the developing device 5 or the non-recovery process has been described above.

  By the way, when the image forming apparatus is a color image forming apparatus, the tandem type image forming apparatus has the image carrier 1, the charging roller 2, and the exposure unit shown in FIG. 1 for each color of cyan, magenta, yellow, and black. 3, an image forming unit including a cleaning device 4, a developing device 5, and the like is provided. For this reason, as described above, the regular determination of the developing device (toner) and the recovery processing or non-collection processing of the residual toner in the developing device 5 according to the determination result are performed for each image forming unit corresponding to each color. Good.

  Further, there is only one charging roller 2, exposure unit 3, cleaning device 4, developing device 5 and the like, and a so-called four-cycle type color using a developing device 5 corresponding to each color of cyan, magenta, yellow, and black. In the case of the image forming apparatus, every time the transfer of the toner image of one color to the intermediate transfer body 8 is completed, the developing device 5 for the residual toner according to the regular product discrimination and the discrimination result as described above, as described above. Recovery processing or non-recovery processing may be performed.

  Note that the black (monochrome) developing device 5 does not cause much image degradation even if it is not a regular product as compared to the color developing device 5.

  Therefore, only the color developing device 5 is subjected to non-recovery processing of residual toner when it is not a genuine product, and is collected into the developing device 5 regardless of whether it is a genuine product when it is a monochrome developing device. It is good also as what performs a process.

  Next, the toner recovery / non-recovery processing will be described with reference to the flowchart shown in FIG.

  In FIG. 5, it is determined in step S101 whether the developing device 5 (toner) is color or monochrome. If it is not color, that is, if it is monochrome (NO in step S101), the process proceeds to step S104 and the negative potential of the developing roller 6 is detected. By continuing the output, the toner removed by the cleaning device 4 after the transfer is sucked and collected by the developing device 5.

  If the developing device 5 is color (YES in step S101), in step S102, the control unit 15 determines whether or not the developing device 5 is a genuine product based on information stored in the memory 12. To determine. This genuine product discrimination process will be described later.

  Next, in step S103, it is determined whether the developing device 5 is a genuine product based on the result of the regular product discrimination process (step S102). If the developing device 5 is a regular product (YES in step S103), the toner removed by the cleaning device 4 after the transfer is sucked and collected in the developing device 5 by continuing the output of the negative potential of the developing roller 6 in step S104. To do.

  If the developing device 5 is not a regular product (NO in step S103), the process proceeds to step S105, and the toner removed by the cleaning device 4 is not collected in the developing device 5 by turning off the negative potential of the developing roller 6. Like that.

  FIG. 6 is a flowchart showing the regular product discrimination process (step S102) of FIG.

  First, in step S201, after the type information of the developing device is read from the memory 12 of the developing device 5, whether the type of the developing device 5 matches the model information stored in the model information storage unit 25a in step S203. Judge whether. If they match (YES in step S203), it is determined in step S204 that the developing device 5 and thus the toner are genuine. If the type of the developing device 5 does not match the model information (NO in step S203), it is determined in step S205 that the developing device 5 and thus the toner is an irregular product.

  By the way, in the embodiment described above, the toner non-recovery processing when it is determined that the developing device 5 (toner) is not a regular product is performed by turning off the developing output voltage of the developing roller 6. The toner non-recovery processing is not limited to this, and other configurations may be used.

  For example, the developing device 5 may be retracted to the right in FIG. 1 so that the toner removed by the cleaning device 4 is not returned to the developing device 5.

  FIG. 7 shows another embodiment of the present invention, and shows an image forming unit of a toner recycling apparatus and an image forming apparatus (for example, a copying machine, a printer, and a facsimile machine) including the toner recycling apparatus.

  The configuration and operation of the image forming unit and the developing device and the cleaning device included in the image forming unit will be briefly described. First, the image forming unit includes a cylindrical image carrier 101 having a known photosensitive layer on the outer periphery. At the time of image formation, the image carrier 101 rotates in the direction of the arrow 151, and each part of the image carrier 101 has a charged area 161, an exposure frame area 162, a development zone 163 (163a and 163b in the drawing), a transfer area 164, It passes through the separation region 165, the cleaning region 166, and the charge removal region 167.

  First, in the charging area 161, the image carrier 101 is charged to a predetermined potential by the charging device 102. The charged image carrier 101 is exposed to light (lm) emitted by an exposure device (not shown) in the subsequent exposure region 162, and a high potential portion having a potential at the time of charging and a low potential portion in which the potential is attenuated by exposure. An electrostatic latent image is formed. The image carrier 101 holding the electrostatic latent image is supplied with a developer from the developing device 103 to the high potential portion or the low potential portion by the developing device 103 in the subsequent developing region 163, and the toner corresponding to the image to be reproduced. An image is formed. This toner image is conveyed to the transfer region 164 as the image carrier 101 moves, and is transferred to a sheet (generally paper) supplied from a sheet supply unit (not shown) by the transfer device 104. The sheet holding the toner image is separated from the image carrier 101 by the separation device 105 in the separation region 165, and then the toner image is fixed by a fixing device (not shown) and discharged to a discharge tray (not shown). All of the toner that has formed a toner image on the image carrier 101 is not transferred to the sheet, and a part of the toner still remains on the image carrier 101 that has passed through the transfer region 164.

  This residual toner is removed by the cleaning device 106 when the image carrier 101 passes through the cleaning region 166. Thereafter, the image carrier 101 moves to the charge removal region 167, where residual charges are removed by the charge removal device 107, and the next image formation is prepared.

  The developing device 103 includes a housing 121 configured by combining a plurality of members. The housing 121 is formed with a developer mixing and stirring path 129 that contains a two-component developer composed of toner and carrier. In the developer mixing and stirring path 129, the bucket roller 120 is rotatably arranged in the direction of an arrow 152 in order to uniformly mix the toner and the carrier and to charge the toner and the carrier to a predetermined polarity by frictional contact. Various well-known bucket rollers 120 can be used, but in this embodiment, a type that conveys the developer from the central portion toward both ends is used.

  A developer conveyance path 130 is formed substantially in parallel with the developer mixing agitation path 129 on the side opposite to the image carrier 101 with the developer mixing agitation path 129 as a boundary, and the developer conveyance path 130 is conveyed to this developer conveyance path 130. A screw 131 is arranged. Unlike the bucket roller 120, the developer conveying screw 131 is configured to convey the developer from both end sides toward the central portion, so that the spiral screw portion on one end side and the helical screw portion on the other end side are separated from the central portion. Are formed in the opposite direction. Further, the wall 123 separating the developer mixing and stirring path 129 and the developer transport path 130 is a communication path (not shown) in the vicinity of both ends and the center of the bucket roller 120 and the developer transport screw 130. ) Is formed. Therefore, in the developing device of this embodiment, the developer is conveyed from the center to both ends by rotating the bucket roller 120 in the direction of the arrow 152 in the developer mixing and stirring path 129, and then is transferred to the bucket roller 120. The developer is transported up and supplied to both ends of the developer transport path 130. Subsequently, the developer transport screw 131 is rotated in the direction of the arrow 153 so that the developer transport path 130 is transported from the both ends toward the center. Finally, the toner is returned from the developer conveying path 130 to the center of the developer mixing and stirring path 129.

  Above the bucket roller 120, a supply roller 125 that sucks and holds a part of the developer scooped up by the bucket roller 120 is disposed. The supply roller 125 is supported so as to be rotatable in the arrow 154 direction. Further, a regulating member 124 provided in the housing 121 is opposed to the outer peripheral surface of the supply roller 125 with a predetermined minute gap (developer regulating gap) 157 therebetween. Therefore, the amount of developer supplied to the supply roller 125 is regulated by the regulating member 124, and a fixed amount of developer is held on the outer peripheral surface of the supply roller 125 that has passed through the position of the regulating member 124.

  A first developing roller 126 is provided between the supply roller 125 and the image carrier 101 to receive the developer held on the supply roller 125 and to contact the image carrier 101 in the first development region 163a. . Under the first developing roller 126, there is provided a second developing roller 127 which receives the developer from the first developing roller 126 and again contacts the developer with the image carrier 101 in the second developing region 163b. It is. These developing rollers 126 and 127 are maintained in non-contact with the image carrier 101 via predetermined minute gaps (developing gaps) 158 and 159, respectively, and are rotatable in the directions of arrows 155 and 156. Accordingly, the developer held on the supply roller 125 is first supplied to the first developing roller 126 and comes into contact with the electrostatic latent image on the image carrier 101 in the first developing region 163a. Develop. Next, the developer is supplied to the second developing roller 127, and again comes into contact with the electrostatic latent image in the second developing region 163b to further develop the electrostatic latent image. For this reason, the electrostatic latent image is developed at a higher density than an image forming apparatus of a type that contacts the developer held on the developing roller only once.

  The developer that has passed through the second developing region 163b is scraped off from the second developing roller 127 by the scraper 122 disposed between the second developing roller 127 and the bucket roller 120, and the developer mixing and stirring path 129 is obtained. To the developer that is being mixed and stirred.

  Thus, in this image forming apparatus, the toner contained in the developer is consumed by the development of the electrostatic latent image. Therefore, in order to keep the density of the finished image constant, the mixing ratio (toner density) of the toner and the carrier is measured, and when the measured toner density falls below a predetermined toner density, Toner must be replenished. For this purpose, a toner density measuring device 128 is provided at the center bottom of the developer conveyance path 130. Further, a toner replenishing portion 160 containing new toner is disposed above the developer conveyance path 130. When the toner density measured by the toner density measuring device 128 is equal to or lower than a predetermined reference density, a toner replenishing unit is provided at a predetermined portion of the developer transport path 130 (preferably at both ends of the developer transport path 130). From 160, toner is dropped and replenished. The replenished toner is transported together with the existing developer through the developer transport path 130 and the developer mixing sales channels 129, and in contact with the carrier in the transport process, is triboelectrically charged.

  Next, the toner recycling apparatus shown in FIG. 7 will be described. The toner recycling device includes a toner return pipe 112 extending from one end outside of the cleaning device 106 toward a corresponding one end outside of the developing device 103 in order to return the toner collected by the cleaning device 106 to the developing device 103. In the present embodiment, the toner return pipe 112 is a cylindrical pipe with both ends closed, and an upper opening (toner intake port) 114 is formed on the upper end of one end located on the side of the cleaning device 106. A lower opening (developer dropping port) is formed in the lower part on the other end side located at the side of the developing device 103. A return screw 113 is disposed in the toner return pipe 112 in order to convey the toner that has entered from the upper opening 114 toward the opposite lower opening. The return screw 113 is drivingly connected to a waste toner recycling motor 170.

  In order to send toner into the upper opening at one end of the toner return pipe 112, the cleaning device 106 transports the collected toner in a direction parallel to the axis of the image carrier 101, and is connected to the transport path 111. And a toner discharge pipe 110 that protrudes horizontally from the side wall of the cleaning device 106, and a toner discharge port (not shown) formed at the tip of the toner discharge pipe 110 is aligned with the upper opening 114. is there.

  On the other hand, an opening is formed in the side wall of the housing 121 forming the developer conveying path 130 in order to send the toner falling from the lower opening on the other end side of the toner return pipe 112 to the developing device 103. Therefore, the toner sent through the toner return pipe 112 is supplied to the developer conveyance path 130.

  The above-described conveying screw 131 extends in the developer conveying path 130 and is conveyed by the rotation of the conveying screw, and is mixed with the developer conveyed through the developer conveying path 130.

  According to the toner recycling apparatus configured as described above, the toner collected by the cleaning apparatus 106 is opened at the upper end at one end of the toner return pipe 112 from the conveyance path 111 in the cleaning apparatus 106 via the toner discharge pipe 110. Drop supplied through the section. The toner dropped and supplied to the toner return pipe 112 is conveyed toward the opposite end by the rotation of the return screw 113 driven by the waste toner recycling motor 170, and supplied to the developer conveyance path 130 from the lower opening. After being mixed with the developer being conveyed through the developer conveying path 130, the developer mixing and agitating path is mixed and agitated by the bucket roller 120, and is brought into contact with the carrier by the mixing action at these places to be frictionally charged. To do. Thereafter, the developer again contacts the image carrier 101 in the first development area 163a and the second development area 163b through the supply roller 125, the first and second development rollers 126, 127, and is used for development. Is done.

  FIG. 8 is a block diagram illustrating an electrical configuration of an image forming apparatus including the developer recycling apparatus of FIG. Since this block diagram is the same as the block diagram shown in FIG. 2 except that the waste toner recycling motor 170 is added, the detailed description is omitted.

  FIG. 9 is a flowchart showing toner collection / non-recovery processing of the image forming apparatus provided with the developer recycling apparatus of FIG.

  In FIG. 9, it is determined in step S301 whether the developing device 103 (toner) is color or monochrome. If it is not color, that is, if it is monochrome (NO in step S301), the process proceeds to step S304. When the developing device 103 is color (YES in step S301), in step S302, the control unit 15 determines whether or not the developing device 103 is a genuine product based on information stored in the memory 12. To determine. This regular product discrimination process is the same as the process shown in FIG.

  Next, in step S303, it is determined whether or not the developing device 103 is a regular product based on the result of the regular product discrimination process (step S302). If the developing device 103 is a regular product (YES in step S303), the process advances to step S304 to drive the waste toner recycling motor 170. In step S305, the toner removed by the cleaning device 106 is rotated by the rotation of the return screw 113. It is conveyed toward the opposite end of the return pipe 112 and collected in the developing device 103.

  If the developing device 103 is not a regular product (NO in step S303), the process proceeds to step S306, and the toner removed by the cleaning device 106 is not collected in the developing device 103 with the waste toner recycling motor 170 kept off. .

  FIG. 10 shows still another embodiment of the present invention, and shows a schematic configuration diagram of a digital color copying machine (hereinafter simply referred to as “copying machine”). This copier is a so-called tandem type copier that forms a color image by multiple transfer of toner images formed by a plurality of image forming units arranged along a transfer belt.

  The copying machine can be roughly divided into an image reader unit 200 that reads an original image and a printer unit 300 that reproduces an image read by the image reader unit 200 on a recording sheet. The image reader unit 200 scans an original on the platen glass 221 and reads it as R, G, and B electrical signals, and a read signal that performs processing such as conversion of the electrical signals obtained thereby into gradation data The processing unit 228 is included. The scanner 222 is driven by the motor 227 to move in the direction of arrow A when reading the document, and scans the document on the platen glass 221 while irradiating it with the exposure lamp 223. The reflected light from the document surface of the irradiation light is collected by the rod lens array 224 and is photoelectrically converted by the contact type CCD color image sensor 225 to be an electrical signal of R, G, and B colors. The read signal processing unit 228 converts this electrical signal into 8-bit gradation data of yellow (Y), magenta (M), cyan (C), and black (K).

The printer unit 300 includes a printer control unit 301, a laser optical system 330, an image forming system 340,
Consists of a transport system 350. Based on the signal output from the read signal processing unit 328, the printer control unit 301 generates a laser diode drive signal for each gradation data of each color, and the respective drive signals of the corresponding printer heads 303C to 303K of the laser optical system 330 are generated. Turn on the laser diode. The photosensitive drums 301 </ b> C to 301 </ b> K to which the laser beam generated thereby is rotated are exposed and scanned.

  The photosensitive drums 301C to 301K are uniformly charged by the charging chargers 302C to 302K, and electrostatic latent images are formed by the exposure scanning described above, and the developing devices 304C to 304K are respectively cyan, magenta, yellow, and black. The electrostatic latent images on the photosensitive drums 301C to 301K are developed with toner. On the other hand, a recording sheet fed from the paper cassette 313 or 314 is conveyed by a transfer belt 310 that is stretched by a driving roller 311 and a driven roller 312 and driven to run at a constant speed, and the photosensitive drums 301C to 301K. The toner images of the respective colors formed in the above are sequentially transferred so as to be superimposed on the recording sheet in response to the transfer electric field from the transfer brushes 305C to 305K. The recording sheet to which the toner image has been transferred is separated from the transfer belt 310 and fixed by a fixing device 315, and then the green sheet is discharged to a paper discharge tray 316.

  In each of the photosensitive drums 301C to 301K, cleaning devices 306C to 306K are arranged on the upstream side in the rotation direction of the charging chargers 302C to 302K. Further, as representatively shown in the photosensitive drum 301C in FIG. 11, the regular color toner or the regular and non-genuine monochrome toners are collected and reused in the vicinity of the cleaning devices 306C to 306K. Waste toner bottles 318 are respectively arranged, and toner is supplied to the developing devices 304C to 304K from a toner supply bottle 317 via a toner supply motor 319.

  In addition, the toner replenishment bottle 317 is provided with a memory 320, and information about whether the toner filled in the toner replenishment bottle 317 is a regular product or an irregular product is written in the memory 320. Yes. Then, the control unit 15 reads the information written in the memory 320 via the toner type detection unit 27 (shown in FIG. 1), and determines whether the toner filled in the toner supply bottle 317 is a genuine product or an unauthorized product. It is determined whether it is a product.

  FIG. 12 is a flowchart showing such a determination process.

  First, in step S401, toner type information is read from the memory 320 of the toner supply bottle 317, and in step S403, the toner type is stored in the model information storage unit 25a (shown in FIG. 1). Determine if they match. If they match (YES in step S403), it is determined in step S404 that the toner is a genuine product. If the toner type does not match the model information (NO in step S403), it is determined in step S405 that the toner is an irregular product.

  When it is determined that the toner is a regular product, the residual color toner on each of the photosensitive drums 301C to 301K removed by the cleaning devices 306C to 306K is collected in a waste toner bottle 318 for reuse. . The waste toner bottle 318 from which the genuine color toner is collected is mounted as a toner supply bottle 317 and is reused. Monochrome toner is collected in the waste toner bottle 318 and reused regardless of whether it is a genuine product or a non-genuine product.

  On the other hand, the color toner determined to be non-genuine is dropped in the transfer belt 310 without being collected in the waste toner bottle 318 for reuse, and is collected in the waste toner collecting unit 370 (FIG. 10). .

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, although it has been described that the residual toner on the photosensitive drum (image carrier) is collected, the residual toner transferred to the transfer belt may be collected. Further, the developer is not limited to toner, and may be applied to collection of ink other than toner or liquid developer.

1 is a schematic cross-sectional view illustrating a configuration of a printing unit of an image forming apparatus according to an embodiment of the present invention. 2 is a block diagram illustrating an electrical configuration of the image forming apparatus. FIG. 6 is a timing chart for explaining the operation when the developing device is a regular product. 6 is a timing chart for explaining the operation when the developing device is not a regular product. 6 is a flowchart illustrating a process for collecting toner removed by a cleaning device. It is a flowchart which shows a regular article discrimination | determination process. It is a schematic sectional drawing of the image creation part of the image forming apparatus which concerns on other embodiment of this invention. FIG. 8 is a block diagram illustrating an electrical configuration of the image forming apparatus in FIG. 7. FIG. 8 is a flowchart illustrating a process of collecting toner removed by a cleaning device, which is executed in the image forming apparatus of FIG. 7. It is a schematic block diagram of the image forming apparatus which concerns on further another embodiment of this invention. FIG. 11 is an enlarged view of a peripheral portion of one photosensitive drum of the image forming apparatus of FIG. 10. FIG. 11 is a flowchart showing a regular product discrimination process executed in the image forming apparatus of FIG. 10. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image carrier 4,106,306C-306K Cleaning device 5,103,304C-304K Developing device 8 Intermediate transfer body 12,320 Memory 15 Control part (Developing device discrimination means)
101 Image carrier 301C to 301K Photosensitive drum 317 Toner supply bottle 318 Waste toner bottle S Recording medium

Claims (6)

An image carrier on which an electrostatic latent image is formed on the surface;
A developing device for developing an electrostatic latent image on the image bearing member as a developed image with a developer,
After transfer to the recording medium or an intermediate transfer member of the developed image, a cleaning means for removing the developer remaining adhered to the surface of the image bearing member or an intermediate transfer member surface,
The pre-granted information to the developing device, a developer discriminating means for the developer to determine whether genuine,
Wherein when it is determined that genuine by the developer discriminating means, developer removed by said cleaning means is recovered to the developing device, so as not to be recovered when it is judged not to be genuine, Control means for controlling the components of the apparatus;
An image forming apparatus comprising: An image carrier on which an electrostatic latent image is formed on the surface;
A developing device for developing the electrostatic latent image on the image carrier as a developed image with a developer;
A cleaning means for removing the developer remaining on the surface of the image carrier or the intermediate transfer member after the development image is transferred to the recording medium or the intermediate transfer member;
Developer discriminating means for discriminating whether or not the developer is a genuine product;
When the developer discriminating unit determines that the product is genuine, the developer removed by the cleaning unit is collected by the developing device, and when the developer discriminating is not genuine, the developer is not collected. Control means for controlling the components of the apparatus;
With
Said control means, said by controlling the developing output voltage of the developing device, an image forming apparatus and controls so that the developer can not be recovered in the developing device. An image carrier on which an electrostatic latent image is formed on the surface;
A developing device for developing the electrostatic latent image on the image carrier as a developed image with a developer;
A cleaning means for removing the developer remaining on the surface of the image carrier or the intermediate transfer member after the development image is transferred to the recording medium or the intermediate transfer member;
Developer discriminating means for discriminating whether or not the developer is a genuine product;
When the developer discriminating unit determines that the product is genuine, the developer removed by the cleaning unit is collected by the developing device, and when the developer discriminating is not genuine, the developer is not collected. Control means for controlling the components of the apparatus;
With
It said control means, by retracting the developing device from a predetermined position, the image forming apparatus characterized by controlling so that the developer can not be recovered in the developing device. A waste developer tank for accumulating the developer removed by the cleaning means;
A developer returning means for returning the developer accumulated in the developer tank to the developing device;
The image forming apparatus according to claim 1, wherein the control unit controls the developer not to be collected by the developing device by not operating the developer returning unit. A monochrome color discriminating means for discriminating whether the developer is monochrome or color;
When the developer is determined to be a monochrome developer by the monochrome color determining means, the control means, regardless of genuine whether determination result by the developer discriminating means, said cleaning means the image forming apparatus according controlled to claims 1 to any one of 4 to developer removed is collected in the developing device by. An image carrier on which an electrostatic latent image is formed on the surface;
A developing device for developing the electrostatic latent image on the image carrier as a developed image with a developer;
A cleaning means for removing the developer remaining on the surface of the image carrier or the intermediate transfer member after the development image is transferred to the recording medium or the intermediate transfer member;
A detachable waste developer container for accumulating the developer removed by the cleaning means;
A developer supply container for supplying the developer to the developing device;
Developer discriminating means for discriminating whether or not the developer is a genuine product according to information previously given to the developer supply container;
When the developer discriminating unit determines that the product is genuine, the developer removed by the cleaning unit is collected in the waste developer container. When the developer discriminating unit is determined not to be genuine, the developer is not collected. Control means for controlling the components of the apparatus;
With
The image forming apparatus, wherein the waste developer container is reusable as the developer supply container.

Images