JP2008026365A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of saving the space within the apparatus body. <P>SOLUTION: The image forming apparatus 10 includes: a photoreceptor 40 on which a latent image is formed; a developing device 44 which develops the latent image formed on the photoreceptor 40; a toner cartridge 50 which is removably provided in the developing device 44 and in which toner to be supplied to the developing device 44 is stored; a waste toner storing part 64c in which waste toner removed from the surface of the photoreceptor 40 is stored; and a controller 36 which controls to collect the waste toner in the waste toner storing part 64c to the toner cartridge 50 in a predetermined timing. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a printer, a copying machine, or a facsimile.

  This type of image forming apparatus is known to include a cleaning device that removes and stores waste toner remaining on the surface of a photoreceptor and the like, and a waste toner collection container that collects the waste toner stored in the cleaning device. It has been. For example, a technique is known in which a waste toner collection container is disposed on the outer periphery of a toner cartridge and the waste toner is aggregated and accumulated on the outer periphery of the waste toner collection container (for example, Patent Document 1).

Japanese Patent No. 3308138

  However, in the above prior art, it is necessary to secure a space for the waste toner collecting container in the toner cartridge, and it is necessary to increase the size of the toner cartridge or reduce the capacity of the supplied toner.

  An object of the present invention is to provide an image forming apparatus that solves the above-described conventional problems and realizes space saving in the apparatus main body.

  In order to achieve the above object, the present invention is characterized by a photosensitive member on which a latent image is formed, a developing device for developing the latent image formed on the photosensitive member with toner, and a detachable attachment to the developing device. A toner container that contains toner to be supplied to the developing device, a waste toner container that contains waste toner removed from the surface of the photoreceptor, and waste toner in the waste toner container. The image forming apparatus includes a control unit that controls the toner container to collect the toner at a predetermined timing. Therefore, space saving in the apparatus main body can be realized.

  Preferably, it has a detection means for detecting the remaining amount of toner in the toner container.

  Preferably, the control means operates when the detection means detects that the remaining amount of toner in the toner container has become a predetermined amount or less. Therefore, mixing of the toner supplied to the developing device and the waste toner is prevented.

  Preferably, a gate for blocking or opening between the toner container and the waste toner collecting unit is provided. Therefore, mixing of the toner supplied to the developing device and the waste toner is prevented.

  Preferably, the control means controls the gate to operate at a predetermined timing.

  Preferably, the toner container has a toner conveying means for conveying toner.

  Preferably, the toner conveying means conveys the waste toner discharged from the waste toner storage unit.

  Preferably, the apparatus includes a driving device that drives the toner conveying unit, and the control unit controls the driving device to be driven at a predetermined timing.

  Preferably, the gate is operated by driving the driving means. Accordingly, the number of driving means can be reduced.

  According to the present invention, since the waste toner in the waste toner container is collected in the toner container at a predetermined timing, the waste toner collection container for collecting the waste toner can be eliminated, and the apparatus Space saving in the body can be realized.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an image forming apparatus 10 according to a first embodiment of the present invention. The image forming apparatus 10 includes an image forming apparatus main body 12. A paper feeding device 14 is disposed below the image forming apparatus main body 12, and a paper discharge unit 16 is disposed above the image forming apparatus main body 12. Is formed.

  The paper feeding device 14 includes a paper tray 18, and a large number of sheets are stacked on the paper tray 18. A feed roll 20 is disposed on the upper end of the paper tray 18, and a roll 22 is provided facing the feed roll 20. The uppermost sheet on the sheet tray 18 is picked up by the feed roll 20, and the sheet is rolled and conveyed by the cooperation of the feed roll 20 and the separating roll 22.

  The sheet conveyed from the sheet tray 18 is temporarily stopped by the registration roller 24, and discharged at a predetermined timing between a photosensitive unit 26 and a transfer unit 28, which will be described later, and through a fixing device 30 by a discharge roller 32. 16 is discharged.

  In the image forming apparatus main body 12, a photoconductor unit 26, a transfer unit 28, a power supply unit 34, and a control device 36 as a control unit are arranged. In the photoreceptor unit 26, for example, four photoreceptors 40 are rotatably supported by the photoreceptor unit main body 64. Around each photoconductor 40 is a charging device 42 as a charging means provided with a charging roll for uniformly charging the photoconductor 40, and a developing means for developing the latent image written on each photoconductor 40 with toner. A developing device 44, a neutralizing device 46 for neutralizing the photoconductor 40 after transfer, and a cleaning device 48 as a toner removing means for removing toner remaining on the photoconductor 40 after the transfer. The photoconductor unit 26 includes four photoconductors 40, a charging device 42, a developing device 44, a charge removal device 46, and a cleaning device 48, and is detachable from the image forming apparatus main body 12.

  The four toner cartridges 50 are detachably connected to the back side of the photoreceptor unit 26. Each toner cartridge 50 is for magenta, yellow, cyan, and black, and is used as a toner container that stores toner of each color supplied to the developing device 44.

  Each of the optical writing devices 56 is composed of a laser exposure device, and is arranged on the back side of the photoconductor unit 26 at a position corresponding to each photoconductor 40, and irradiates the uniformly charged photoconductor 40 with a laser. Thus, a latent image is formed.

  The transfer unit 28 is on the front side of the photoconductor unit 26 and is arranged in the vertical direction facing the photoconductor unit 26. In the transfer unit 28, a conveyance belt 60 is hung on two support rolls 58 provided in the vertical direction. Further, a transfer roll 62 is provided so as to face each photoconductor 40 with the conveyance belt 60 interposed therebetween.

  The print density sensor 52 is provided in the vicinity of each photoconductor 40, detects the density of each color toner image transferred to the paper, and outputs the detection result to the control device 36. The print number sensor 54 detects the number of printed sheets and outputs the detection result to the control device 36.

  Therefore, each photoconductor 40 is uniformly charged by the charging device 42, a latent image is formed by the optical writing device 56, and the latent image is visualized by toner by the developing device 44. The toner images formed on the respective photoconductors 40 are transferred onto the conveyed paper by the transfer roller 62 of the transfer unit 28 in order from below, and are fixed on the paper by the fixing device 30.

  Next, details of the photosensitive unit 26 will be described with reference to FIG. As shown in FIG. 2, the photoconductor unit 26 has the photoconductor unit main body 64 as described above, and the inside of the photoconductor unit main body 64 is divided into, for example, the developing device 44 and the cleaning device 48 described above. ing.

  The developing device 44 includes a toner supply unit 64a, and a developing roll 66 is disposed in the vicinity of the photoreceptor 40 in the toner supply unit 64a. Further, a through hole 64b connected to the toner cartridge 50 is formed in the toner supply part 64a.

  The first agitating / conveying auger 67a and the second agitating / conveying auger 67b are disposed below the developing roller 64 along the axial direction of the developing roller 66, and are respectively rotatably supported on the peripheral wall of the toner supply unit 64a. ing. When the first agitating / conveying auger 67a and the second agitating / conveying auger 67b are respectively rotated, the toner stored in the toner supply unit 64a is conveyed in the direction of the developing roll 66 while being agitated.

  The cleaning device 48 includes a cleaning blade 68 and a waste toner container 64c. The cleaning blade 68 scrapes off and removes residual toner adhering to the surface of the photoreceptor 40, and the waste toner storage unit 64 c stores the waste toner removed by the cleaning blade 68. The waste toner container 64c is provided with an opening 64d communicating with the toner supply unit 64a of the developing device 44, and a waste toner auger 69 for conveying the waste toner to the opening 64d is disposed. ing.

  The toner cartridge 50 includes a toner cartridge main body 70, and the toner cartridge main body 70 is formed with a toner storage portion 70 a that stores toner and a convex portion 70 b that protrudes from a side surface of the toner cartridge main body 70. The convex portion 70 b communicates with the toner storage portion 70 a and is formed so as to be connected to the through hole 64 d of the developing device 44. Further, an opening 70c is formed on the upper surface of the convex portion 70b to communicate the toner storage portion 70a with the outside of the toner cartridge body 70.

  The auger 72 is rotatably provided in the toner cartridge main body 70, and is used as a toner transport unit that transports toner in the toner storage portion 72. A motor 74 (shown in FIG. 6) is connected to one end of the auger 72 and is used as a drive device that rotates the auger 72. The motor 74 is a forward / reverse motor capable of normal rotation and reverse rotation, and the rotation direction is controlled by an instruction from the control device 36 described above.

  The gate 76 is rotatably provided on the inner wall surface of the toner supply unit 64a and is used as a gate for blocking or opening between the waste toner storage unit 64c of the cleaning device 48 and the toner storage unit 70a of the toner cartridge 50. It is done. The gate 76 is formed in an L shape having a vertical plane and a horizontal plane, and is arranged so that a part of the horizontal plane of the gate 76 covers the opening 64e.

  Further, as shown in FIG. 3, the gate 76 is fixed to a support shaft 78 that is rotatably provided on the photoconductor unit main body 64. The support shaft 78 is provided with a first gear 80 via a torque limiter 82, and a notch 78a is formed in part. The second gear 84 is connected to a gear (not shown) provided on the output shaft of the motor 74 and rotates in the same direction as the rotation direction of the motor 74. The connection gear 86 is arranged so as to connect the first gear 80 and the second gear 84 and to transmit the drive of the second gear 84 to the first gear 80. The solenoid 88 is disposed in the vicinity of the gate 76, and includes a movable piece 88a that operates when in an excited state (ON), and a stopper 88b that engages with the notch 78a by the operation of the movable piece 88a. Have. The solenoid 88 is controlled by an instruction from the control device 36.

  As shown in FIGS. 3A and 3C, when the solenoid 88 is in a non-excited state (OFF), the stopper 88b and the notch 78a are engaged to prevent the gate 76 from rotating. Yes. At this time, the drive of the motor 74 transmitted to the second gear 84, the connecting gear 86, and the first gear 80 is blocked by the sliding of the torque limiter 82.

  On the other hand, as shown in FIG. 3B, when the solenoid 88 is in an excited state (ON), the movable piece 88a is pulled in, the engagement between the stopper 88b and the notch 78a is released, and the motor 74 is driven. The gate 78 is rotated by being transmitted to the second gear 84, the connecting gear 86, the first gear 80, and the support shaft 78. That is, the gate 76 operates by driving the motor 74.

  In this manner, by driving the auger 72 and the gate 76 by the motor 74, the driving means can be reduced as compared with the case where the auger 72 and the gate 76 are provided with driving means. Accordingly, cost reduction and space saving in the image forming apparatus main body 12 can be realized.

  As shown in FIG. 4, the control device 36 is used as detection means for detecting the remaining amount of toner in the toner cartridge 50. More specifically, the control device 36 includes a control unit 36a that controls each movable unit and a storage unit 36b that stores detection results output from each sensor (such as the print density sensor 52 and the print number sensor 54). . The control unit 36a calculates the remaining amount of toner in the toner cartridge 50 based on the detection result of each sensor stored in the storage unit 36b, and controls the operation of the auger 72 and the gate 76 based on the calculation result.

  In addition, a toner remaining amount detector is provided in the toner cartridge 50 or the developing device 44. For example, a constant current source (resistance value) due to a change in the developer amount between two points in the toner cartridge 50 or the developing device 44 is provided. By detecting the change, the remaining amount of toner may be output to the control device 36 as a detected voltage value. The toner remaining amount detector may be a piezoelectric element.

Next, a toner supply method and a waste toner collection method will be described with reference to FIGS.
FIG. 5 shows toner supply and waste toner recovery processing (S10).

  In step S100, as shown in FIG. 6A, the control device 36 drives the motor 74 in the normal rotation direction (the direction of arrow a in FIG. 6A). At this time, the toner in the toner container 70a is conveyed in the direction of the developing device 44 (in the direction of arrow A in FIG. 6A) by the rotation of the auger 72, and the toner supply portion 64a of the developing device 44 through the opening 70c. To be supplied.

  In step S105, the control device 36 determines whether or not the remaining amount of toner in the toner cartridge 50 is equal to or less than a predetermined amount based on the detection results output from the print density sensor 52 and the print number sensor 54. If the amount is equal to or greater than the predetermined amount, the process proceeds to step S100 again. If the remaining amount of toner is equal to or less than the predetermined amount, for example, if it is determined that the remaining amount of toner is 0 (none), the process proceeds to step S110. .

  In step S110, as shown in FIG. 6B, the control device 36 drives the motor 74 in the reverse rotation direction (the direction of arrow b in FIG. 6B) to move the auger 72 in the opposite direction to step S100 described above. Rotate. Further, the control device 36 sets the solenoid 88 in an excited state (ON), rotates the gate 76 by driving the motor 74, and opens the space between the waste toner container 64c and the toner cartridge 50.

  In step S115, the control device 36 reverses the auger 72 by the motor 74 for a predetermined time, and collects the waste toner in the waste toner storage unit 64c in the toner storage unit 70a. That is, the toner in the waste toner container 64c is transported to the second opening 64e by the waste toner auger 69, and further collected into the toner container 70a of the toner cartridge 50 through the opening 70c (arrow in FIG. 6). Conveyed in the B direction). In this way, by rotating the auger 72 for a predetermined time, almost all the waste toner in the waste toner container 64c moves into the toner container 70a of the toner cartridge 50.

  In step S <b> 120, the control device 36 activates the gate 76 by driving the motor 74 with the solenoid 88 in an excited state (ON), and the gate 76 blocks the waste toner container 64 c from the toner cartridge 50. Subsequently, the user removes the toner cartridge 50 from the image forming apparatus main body 12 and collects the waste toner.

  The waste toner auger 69 may be always rotated or may be rotated only when the waste toner is collected.

  As described above, the image forming apparatus 10 of the present invention collects the waste toner in the waste toner container 64c in the toner container 70a of the toner cartridge 50, thereby eliminating the toner collection container for collecting the waste toner. be able to. Accordingly, it is possible to realize space saving in the image forming apparatus main body 12 without increasing the size of the toner cartridge or reducing the capacity of the supplied toner, and the structure of the toner cartridge 50 can be simplified.

  Further, when the control device 36 operates at a predetermined timing, that is, when the remaining amount of toner in the toner cartridge 50 becomes a predetermined amount or less, the gate 76 is operated to collect waste toner, so that the toner cartridge 50 and the developing device 44 are recovered. Mixing of toner to be supplied to waste toner and waste toner can be prevented. Further, the supply toner and waste toner are transported by the auger 72, that is, the toner transport means is used in common for the supply toner and waste toner, thereby simplifying the structure of the photoreceptor unit 26 and realizing cost reduction. Can do.

Next, a second embodiment according to the present invention will be described with reference to FIG.
As shown in FIG. 7, the photoreceptor unit main body 64 according to the present embodiment includes a waste toner storage portion 64 c that stores waste toner removed by the cleaning blade 68 and a convex portion that protrudes from the side surface of the photoreceptor unit main body 64. 64e is formed. The convex portion 64e communicates with the waste toner accommodating portion 64c and is formed so as to be connected to a through hole 70d of the toner cartridge main body 70 described later. Further, a waste toner discharge port 64f is formed on the lower surface of the convex portion 64e.

  The second waste toner auger 90 is rotatably provided on the photoreceptor unit main body 64 and is used as second waste toner transport means for transporting the waste toner in the waste toner container 64c. At one end of the second waste toner auger 90, a waste toner motor (not shown) is provided as a driving means for rotating the waste toner auger 90.

  The toner cartridge 50 includes a toner cartridge main body 70, and the toner cartridge main body 70 is formed with a toner storage portion 70 a for storing toner and a convex portion 70 b having an opening 70 c on the lower surface. Further, the toner cartridge main body 70 is provided with a through hole 70d for communicating the outside of the toner cartridge main body 70 and the toner containing portion 70a. The through hole 70d is connected to the convex portion 64e of the photosensitive unit main body 64 described above. It is formed to do.

  Accordingly, when the control device 36 determines that the remaining amount of toner in the toner cartridge 50 is equal to or less than the predetermined amount, the control device 36 drives a waste toner motor (not shown), and the waste toner auger 69 and the second toner auger 69 described above. The waste toner auger 90 is rotated. As a result, the waste toner in the waste toner container 64e is conveyed in the direction of the toner cartridge 50 (in the direction of arrow C in FIG. 7) and is collected in the toner container 70a of the toner cartridge 50 through the toner discharge port 64g. . By rotating the second waste toner auger 90 for a predetermined time, almost all waste toner in the waste toner storage portion 64c moves into the toner storage portion 70a.

  As described above, in the present embodiment, it is possible to realize the collection of the waste toner without providing a gate that cuts off or opens between the waste toner storage portion 64c and the toner storage portion 70a and a driving unit that drives the gate. it can.

  As described above, the present invention can be used for an image forming apparatus having a toner container in which toner to be supplied to a developing device is accommodated.

1 is a side view showing an image forming apparatus according to an embodiment of the present invention. 1 is a longitudinal sectional view showing a photosensitive unit and a toner cartridge of an image forming apparatus according to an embodiment of the present invention. It is a schematic diagram explaining operation | movement of the gate which concerns on embodiment of this invention, (a) is before rotation of a gate, (b) is during rotation of a gate, (c) is the state after rotation of a gate. Show. It is a block diagram which shows the function structure of the control apparatus which concerns on embodiment of this invention. 6 is a flowchart illustrating toner supply and waste toner collection processing executed by a control device according to an embodiment of the present invention. 4A and 4B are diagrams for explaining a toner supply and waste toner recovery method in the image forming apparatus according to the embodiment of the present invention, where FIG. FIG. 5 is a longitudinal sectional view showing a photosensitive unit and a toner cartridge of an image forming apparatus according to a second embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 26 Photoconductor unit 36 Control apparatus 40 Photoconductor 44 Developing apparatus 50 Toner cartridge 52 Print density sensor 54 Print number sensor 64 Photoconductor unit main body 64c Waste toner storage part 70 Toner cartridge main body 70a Toner storage part 72 Auger 74 Motor 76 gate

Claims (9)

A photoreceptor on which a latent image is formed;
A developing device for developing the latent image formed on the photoreceptor with toner;
A toner container that is detachably provided in the developing device and stores toner to be supplied to the developing device;
A waste toner storage unit for storing waste toner removed from the surface of the photoreceptor;
Control means for controlling the waste toner in the waste toner container to be collected in the toner container at a predetermined timing;
An image forming apparatus comprising:   The image forming apparatus according to claim 1, further comprising a detecting unit configured to detect a remaining amount of toner in the toner container.   The image forming apparatus according to claim 2, wherein the control unit is activated when the detection unit detects that the remaining amount of toner in the toner container has become a predetermined amount or less.   The image forming apparatus according to claim 1, further comprising a gate that blocks or opens between the toner container and the waste toner collecting unit.   The image forming apparatus according to claim 4, wherein the control unit controls the gate to operate at a predetermined timing.   The image forming apparatus according to claim 1, wherein the toner container includes a toner transport unit that transports toner.   The image forming apparatus according to claim 6, wherein the toner transport unit transports waste toner discharged from the waste toner storage unit.   The image forming apparatus according to claim 6, further comprising a driving device that drives the toner conveying unit, wherein the control unit controls the driving device to be driven at a predetermined timing.   The image forming apparatus according to claim 8, wherein the gate is operated by driving of the driving unit.

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