JP2010237422A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus whose structure is simplified. <P>SOLUTION: The image forming apparatus 1 includes: a waste toner container 101 for storing waste toner; a power supply mechanism 190; waste toner conveying means 105 to 109 that are driven by drive power supplied by the drive power supply mechanisms 190 and convey waste toner; a first displacing section 110 that is periodically displaced in conjunction with a conveying screw 109 composing the waste toner conveying means; a second displacing section 120 that is displaced according to the accumulation level of waste toner in the waste toner container 101; and a detection means 144 that outputs detection results corresponding to the combination of the displacement of the first and second displacing sections 110 and 120; and decision means S100 to S108 that separately determine, based on the detection signal, whether the driving force supply mechanism 190 or the conveying screw 109 is in an abnormal condition and whether the amount of waste toner accumulated in the toner container 101 has reached a predetermined accumulation level. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  Patent Document 1 discloses an example of a conventional image forming apparatus. This image forming apparatus forms an image on a recording medium by transferring a toner image to the recording medium, and includes a waste toner container for storing waste toner that has not been transferred to the recording medium; A conveying screw provided in the container.

  The conveying screw has a rotation shaft that is rotatably supported on one side wall and the other side wall of the waste toner container, and a wing provided spirally around the rotation axis. One end of the rotating shaft protrudes from one side wall of the waste toner container, and the other end of the rotating shaft is connected to a drive source. Between the other side wall of the waste toner container and the rotating shaft, a coil spring that biases the rotating shaft toward the one side wall is disposed in a compressed state.

  In this image forming apparatus, the waste toner is transferred from one of the waste toner containers to the other by being driven by a drive source and rotating the conveying screw around the rotation axis. When the rotating shaft of the conveying screw is damaged, the one end of the rotating shaft is displaced so as to further protrude from one side wall of the waste toner container by the restoring force of the coil spring, and the displacement is detected by the sensor. Thus, the breakage of the conveying screw is detected.

JP 2009-8820 A

  However, since the conventional image forming apparatus is configured to detect only the breakage of the conveying screw itself, for example, a driving force transmission member such as a transmission gear or a cleaning roller is interposed between the conveying screw and a driving source. In the case of being present, it is not possible to detect a problem occurring upstream of the conveying screw. For this reason, another detection means for detecting a problem on the upstream side of the conveying screw is required, resulting in complication of the apparatus configuration.

  Further, this type of image forming apparatus requires another detection means for detecting the accumulation state of the waste toner in the waste toner container, which also leads to a complicated apparatus configuration.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus capable of simplifying the configuration of the apparatus.

An image forming apparatus of the present invention is an image forming apparatus that forms an image on the recording medium by transferring a toner image to the recording medium,
A waste toner container for storing waste toner that has not been transferred to the recording medium;
A driving force supply mechanism for supplying a driving force of a driving source;
Waste toner transfer means that is driven by a driving force supplied by the driving force supply mechanism and transfers the waste toner from the outside to the inside of the waste toner container and / or from one to the other inside the waste toner container; ,
A first displacement portion that is periodically displaced in conjunction with the waste toner transfer means;
A second displacement portion that is displaced according to a state of accumulation of the waste toner in the waste toner container;
Detection means for outputting a detection result corresponding to a combination of a displacement state of the first displacement portion and a displacement state of the second displacement portion;
Based on the detection result, it is distinguished whether there is an abnormality in the driving force supply mechanism or the waste toner transfer means and whether the waste toner has reached a specific accumulation state in the waste toner container. And determining means for determining possible (claim 1).

  According to the image forming apparatus of the present invention, the detection unit outputs a detection result corresponding to the combination of the displacement state of the first displacement unit and the displacement state of the second displacement unit. The type of judgment (abnormality of the driving force supply mechanism or waste toner transfer means, toner accumulation state) can be distinguished.

  When there is no abnormality in the driving force supply mechanism or the waste toner transfer means (hereinafter referred to as “waste toner transfer means”), the first displacement portion is periodically displaced. For this reason, a detection means outputs the detection result with a periodic fluctuation | variation corresponding to the periodic displacement of a 1st displacement part. On the other hand, when an abnormality such as a failure occurs in the waste toner transfer means and the waste toner transfer means stops, the first displacement portion is not periodically displaced. For this reason, a detection means outputs the detection result without a periodic fluctuation. As a result, the determination unit can immediately determine that there is an abnormality in the waste toner transfer unit or the like based on the difference between the detection results.

  Further, when there is no abnormality in the waste toner transfer means or the like, when the waste toner reaches a specific accumulation state in the waste toner container, the second displacement portion is displaced accordingly. At this time, since the first displacement part continues the periodic displacement, the detection means outputs a detection result that has a periodic variation and has a difference corresponding to the displacement of the second displacement part. As a result, the determination unit can immediately determine that the waste toner has reached a specific accumulation state based on the difference between the detection results. In other words, in the case of the conventional technique, two detection means are necessary to make such two types of determinations. In the present invention, the two types of determinations can be made distinguishable by one detection unit.

  Therefore, according to the image forming apparatus of the present invention, the apparatus configuration can be simplified, and as a result, the manufacturing cost can be reduced.

  In the image forming apparatus of the present invention, the detection means has a light emitting portion and a light receiving portion facing each other with a gap therebetween, and detects blocking or opening of an optical path provided between the light emitting portion and the light receiving portion. possible. The first displacement unit has a first shielding unit that can take a position for shielding the optical path by the displacement and a position for opening the optical path, and the second displacement unit is a case where the waste toner has not reached a specific accumulation state. In this case, a position where the optical path is shielded and a position where the optical path is opened can be taken by being displaced integrally with the first shielding portion, and when the waste toner reaches a specific accumulation state, it is separated from the first shielding portion. It is desirable to have a second shielding part that is displaced to a position that opens the optical path.

  According to this configuration, the detection means outputs a detection result corresponding to shielding or opening of the optical path.

  When the waste toner transfer unit or the like is operating normally, the detection unit outputs a detection result that is periodically switched because the first blocking unit periodically blocks the optical path. On the other hand, when the waste toner transfer unit or the like stops due to an abnormality such as a failure, the first shielding unit remains to shield or open the optical path, so that the detection unit outputs a detection result that does not vary.

  Further, when the waste toner has not reached a specific accumulation state in the waste toner container, the second shielding portion is periodically displaced together with the first shielding portion to shield the optical path. On the other hand, when the waste toner reaches a specific accumulation state, only the first shielding portion is periodically displaced to shield the optical path. For this reason, a detection means outputs the detection result from which the pattern of 1 period of a signal waveform differs in said two cases.

  As described above, the detection unit can output a detection result having a clear difference corresponding to each of the abnormality of the waste toner transfer unit and the accumulation state of the toner. For this reason, two types of determination (abnormality of the waste toner transfer unit, toner accumulation state) can be efficiently and accurately performed by one detection unit.

  In the image forming apparatus of the present invention, the first displacement portion is periodically engaged with the waste toner transfer means via the first passive portion, the first passive portion engaging with the waste toner transfer means and receiving the driving force. The first shielding part that is vertically displaced and shields or opens the optical path, and the first connection part that integrally connects the first passive part and the first shielding part. The second displacement portion includes a second passive portion provided at a position in contact with the waste toner, a second shielding portion, and a second connection portion that integrally connects the second passive portion and the second shielding portion. Can be. Further, the second passive portion is formed so that the vertical displacement associated with the displacement of the second shielding portion is not restrained until the waste toner is accumulated, but is held at the lower position when the waste toner is accumulated. The second shield part is in contact with the first shield part from above by its own weight while the second passive part is not restrained in the vertical displacement associated with the displacement of the second shield part, and the first shield part It is desirable that the first passive portion is formed so as to be held at a position away from the first shielding portion when the second passive portion is held at the lower position while being displaced in the vertical direction integrally with the portion. (Claim 3).

  According to this configuration, by using the fact that the balance between the second shielding part and the second passive part changes due to waste toner accumulated on the second passive part, the second passive part is held at the lower position, Since it can be easily realized to hold the second shielding part at a position away from the first shielding part, the apparatus configuration can be further simplified.

  In the image forming apparatus of the present invention, a cutout in which the first shielding portion is accommodated is formed across the one side surface and the lower surface of the second shielding portion as seen in a cross section in the direction along the optical path. It is desirable that the cross-sectional shape is such that it does not protrude in a direction parallel to the optical path with respect to the second shielding part in a state of being accommodated in the notch.

  According to this structure, since the width | variety of a 1st, 2 shielding part can be narrowed, a light emission part and a light-receiving part can be made to approach. As a result, it is possible to reduce the size of the detection means and hence the size of the device.

  In the image forming apparatus of the present invention, the second connection portion extends from the second passive portion toward the downstream side in the direction in which the waste toner is transferred, and the first shielding portion and the second shielding portion are the second passive portion. It is desirable that the toner is disposed away from the downstream side in the direction in which the waste toner is transferred.

  According to this configuration, even when the waste toner is accumulated on the second passive portion, it is possible to make it difficult for the waste toner to reach the first shielding portion and the second shielding portion, thereby suppressing a decrease in detection accuracy of the detection means. it can.

  In the image forming apparatus of the present invention, the internal space of the waste toner container is defined between the second passive unit, the first shielding unit, and the second shielding unit, and the space on the second passive unit side and the first and second shielding units. It is desirable to provide a partition wall that partitions into a space on the part side.

  According to this configuration, even when waste toner accumulates on the second passive portion, the partition wall can reliably prevent the waste toner from reaching the first shielding portion and the second shielding portion. A decrease in accuracy can be further suppressed.

  In the image forming apparatus of the present invention, when only the first shielding unit shields the optical path with respect to the time required for one shielding when the optical path is shielded while the first shielding unit and the second shielding unit are in contact with each other, It is desirable that the sizes of the first shielding part and the second shielding part facing the optical path are set so that the time required for one shielding is shortened.

  According to this configuration, the detection means has a difference that can be easily distinguished between when the first and second shielding portions are periodically displaced and when only the first shielding portion is periodically displaced. Since the detection result is output, the determination by the determination means can be performed more accurately.

  In the image forming apparatus of the present invention, the determination unit determines that “the driving force supply mechanism or the waste toner transfer unit is abnormal” when the detection result does not have periodic fluctuations, and the detection result is periodic. If there is a slight fluctuation, it is determined that “the driving force supply mechanism and the waste toner transfer means are not abnormal”, and if the duration of one light path shielding in the detection result is longer than the threshold value, On the other hand, if it is determined that the specific accumulation state has not been reached, and if the duration of one light path blocking in the detection result is equal to or less than the threshold value, it may be determined that the waste toner has reached the specific accumulation state. Desirable (Claim 8).

  By providing the determination means having the specific configuration described above, the operational effects of the present invention can be reliably achieved.

  The image forming apparatus of the present invention includes a housing, and a waste toner collecting unit in which the waste toner container, the driving force supply mechanism, the waste toner transfer means, the first displacement portion and the second displacement portion are detachably provided to the housing. Preferably, the detection means and the determination means are provided on the housing side (claim 9).

  According to this configuration, when the waste toner recovery unit is removed, the determination unit determines that there is an abnormality in the waste toner transfer unit and the like, so that the image forming apparatus operates without the waste toner recovery unit attached. It is possible to prevent malfunctions.

It is a schematic sectional drawing of the image forming apparatus of an Example. 1 is a perspective view of a waste toner collecting unit according to an image forming apparatus of an embodiment. FIG. 3 is a perspective view of the waste toner collecting unit according to the image forming apparatus of the embodiment (showing a state where a front upper cover, a cleaning roller, and a scraping roller are removed). FIG. 4 is a top view of the waste toner collecting unit according to the image forming apparatus of the embodiment (showing a state where the front and rear upper covers, the cleaning roller, and the scraping roller are removed). 1 is an exploded perspective view of a waste toner recovery unit according to an image forming apparatus of an embodiment. 1 is a perspective view of a front upper cover according to an image forming apparatus of an embodiment. FIG. 3 is an enlarged perspective view of a main part of the waste toner collecting unit according to the image forming apparatus of the embodiment (showing a conveying screw, a first displacement part, and a second displacement part). FIG. 4 is a perspective view illustrating the image forming apparatus according to the exemplary embodiment with a conveying screw, a first displacement portion, and a second displacement portion separated from each other. FIG. 6 is an enlarged cross-sectional view of a main part for explaining the displacement of the first displacement portion and the second displacement portion according to the rotation of the conveying screw in the image forming apparatus of the embodiment. FIG. 6 is an enlarged cross-sectional view of a main part for explaining the displacement of the first displacement portion and the second displacement portion according to the rotation of the conveying screw in the image forming apparatus of the embodiment. FIG. 4 is an enlarged cross-sectional view of a main part for explaining the displacement of a second displacement part associated with the accumulation of waste toner in the image forming apparatus of the example. FIG. 4 is an enlarged cross-sectional view of a main part for explaining the displacement of a second displacement part associated with the accumulation of waste toner in the image forming apparatus of the example. FIG. 4 is an enlarged cross-sectional view of a main part for explaining the displacement of the first displacement portion and the second displacement portion according to the rotation of the conveying screw and the accumulation of waste toner in the image forming apparatus of the embodiment. 1 is a block diagram illustrating a control system according to an image forming apparatus of an embodiment. 1 is a block diagram illustrating an outline of a sensor control unit according to an image forming apparatus of an embodiment. 6 is a flowchart of a determination program according to the image forming apparatus of the embodiment. 6 is a graph illustrating an example of a detection result by a detection unit according to the image forming apparatus of the embodiment (represents a relationship between a signal output from the sensor control unit and time). 6 is a graph illustrating an example of a detection result by a detection unit according to the image forming apparatus of the embodiment (represents a relationship between a signal output from the sensor control unit and time). 6 is a graph illustrating an example of a detection result by a detection unit according to the image forming apparatus of the embodiment (represents a relationship between a signal output from the sensor control unit and time). 6 is a graph illustrating an example of a detection result by a detection unit according to the image forming apparatus of the embodiment (represents a relationship between a signal output from the sensor control unit and time).

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings.

(Example)
As shown in FIG. 1, a printer 1 as an example of an image forming apparatus according to an embodiment uses a color laser that forms an image having a plurality of colors on a sheet (including an OHP sheet) as a recording medium by an electrophotographic method. It is a printer. In FIG. 1, the right side of the paper is defined as the front side of the apparatus, and the left side of the paper is defined as the rear side of the apparatus. Further, when the device is viewed from the front side, the side that comes to the left hand (the front side of the paper) is defined as the left side, and the opposite side is defined as the right side, and the front, rear, left, and right directions are displayed. 2 to 20 are displayed in correspondence with the respective directions shown in FIG. 1. Hereinafter, each component provided in the printer 1 will be described with reference to FIG.

1. Schematic Configuration of Printer The housing 3 is a substantially box-shaped body, and a frame member (not shown) is provided inside thereof. The frame member is assembled with a paper feeding unit 20, an image forming unit 10, a transport unit 30, a fixing device 80, a waste toner collecting unit 100, and the like. The image forming unit 10 is located substantially at the center of the housing 3.

  On the upper surface side of the housing 3, a discharge tray 5 is provided on which a sheet discharged from the discharge rollers 28 and 29 after image formation is placed. In addition, a front cover 6 that can be opened and closed with the lower end side as a swing center axis is provided on the front surface of the housing 3. The image forming unit 10 and the transport unit 30 are configured to be detachable from the frame member with the front cover 6 opened. The waste toner collecting unit 100 is also configured to be detachable from the frame member in a state where the image forming unit 10 and the transport unit 30 are detached from the housing 3. Note that a specific configuration in which the image forming unit 10, the conveyance unit 30, and the waste toner collection unit 100 can be attached to and detached from the frame member is well known, and thus description thereof is omitted.

2. Paper Feed Unit The paper feed unit 20 forms an image of a paper feed tray 21 that is detachably stored below the housing 3, and that is provided above the front end of the paper feed tray 21 and placed on the paper feed tray 21. A sheet feeding roller 22 that feeds (conveys) the sheet 10 and a separation pad 23 that separates the sheets fed by the sheet feeding roller 22 by giving a predetermined conveyance resistance to the sheets. Yes.

  Then, in the sheet conveyance path P (indicated by a thick two-dot chain line in FIG. 1), the sheet is conveyed to the image forming unit 10 while curving in a substantially U shape at a portion that turns to a substantially U shape in front. Conveying rollers 24 and 25 are provided for applying a conveying force to the sheet to be printed.

  Further, on the downstream side of the conveyance path P with respect to the conveyance rollers 24 and 25, the skew of the sheet is corrected by contacting the leading edge of the sheet conveyed by the conveyance rollers 24 and 25, and then the sheet is further removed. Registration rollers 26 and 27 for conveying the image forming unit 10 toward the image forming unit 10 are provided.

3. Transport Unit The transport unit 30 is disposed between the lower paper feed tray 21 and the upper image forming unit 10 and includes a transport belt 33 and transfer rollers 73K, 73Y, 73M, and 73C.

  The conveyance belt 33 is wound around a driving roller 31 positioned below the rear end side of the image forming unit 10 and a driven roller 32 positioned below the front end side of the image forming unit 10. The driving roller 31 rotates in synchronization with the registration rollers 26 and 27 of the paper feeding unit 20, so that the conveying belt 33 circulates between the driving roller 31 and the driven roller 32. The upper surface of the conveyance belt 33 is disposed substantially horizontally immediately below the image forming unit 10, and is a sheet conveyance surface 33 </ b> A that contacts the back surface of the sheet and conveys the sheet along the conveyance path P. Yes.

  The transfer rollers 73 </ b> K to 73 </ b> C are provided in the transport unit 30 in a state where the transfer rollers 73 </ b> K to 73 </ b> C are in contact with the transport belt 33 from the back surface side of the sheet transport surface 33 </ b> A. Since the conveyor belt 33 is made of conductive rubber, the conveyor belt 33 is also charged by a negative charge (transfer voltage) applied to each of the transfer rollers 73K to 73C. Thus, the transport belt 33 can transport the paper along the transport path P while adsorbing the paper to the paper transport surface 33A by electrostatic force.

4). Image Forming Unit The image forming unit 10 is a so-called direct tandem type capable of color printing, and includes four process cartridges 70K, 70Y, 70M, 70C and the like, a scanner unit 60, and the like. The scanner unit 60 is disposed at the uppermost position inside the housing 3. The four process cartridges 70K, 70Y, 70M, and 70C correspond to toners (developers) of four colors, black, yellow, magenta, and cyan, and are arranged in series from the upstream side to the downstream side of the sheet conveying surface 33A. ing.

4.1. Scanner Unit The scanner unit 60 includes a laser light source, a polygon mirror, an fθ lens, a reflecting mirror, and the like. The laser beam emitted from the laser light source is deflected by the polygon mirror, passes through the fθ lens, and then the optical path is turned back by the reflecting mirror, and further, the optical path is bent downward by the reflecting mirror, whereby the process is performed. Irradiation is performed on the surface of the photosensitive drum 71 provided in each of the cartridges 70K to 70C to form an electrostatic latent image.

4.2. Process Cartridge Since the process cartridges 70K to 70C are the same except for the color of the toner as the colorant and the others are the same, the structure of the process cartridge 70C will be described below as an example.

  The process cartridge 70C includes a known photosensitive drum 71, a charger 72, a toner cartridge 74, and the like.

  The toner cartridge 74 includes a toner storage chamber 74A in which toner is stored, a supply roller 74B, a development roller 74C, and the like. The toner in the toner storage chamber 74A is supplied to the developing roller 74C side by the rotation of the supply roller 74B, is carried on the surface of the developing roller 74C, and is adjusted to a predetermined thickness by the layer thickness regulating blade 74D. It is supplied to the surface of the photosensitive drum 71. The photosensitive drum 71 is disposed on the opposite side of the transfer roller 73 </ b> C across the paper conveyance surface 33 </ b> A of the conveyance belt 33.

5). Fixing Device The fixing device 80 is disposed on the downstream side of the process cartridges 70K to 70C in the paper transport path P. The fixing device 80 includes a heating roller 81 and a pressure roller 82. The heating roller 81 is disposed on the image forming surface side of the paper and rotates in synchronization with the transport belt 33 and the like, and applies a transport force to the paper while heating the toner transferred onto the paper. On the other hand, the pressure roller 82 is disposed on the opposite side of the heating roller 81 with the sheet interposed therebetween, and is driven to rotate while pressing the sheet toward the heating roller 81 side. As a result, the fixing device 80 heats and melts the toner transferred onto the paper to fix it on the paper, and conveys the paper downstream of the conveyance path P. The conveyance path P is curved in a substantially U shape toward the upper side on the downstream side of the fixing device 80. Discharge rollers 28 and 29 for discharging the sheet on which the image is formed to the discharge tray 5 are provided immediately before the discharge tray 5 on the most downstream side of the transport path P.

6). Outline of Image Forming Operation In the printer 1 of the embodiment having such a configuration, an image is formed on a sheet as follows. That is, when the image forming operation is started, the paper feeding unit 20 and the conveyance unit 30 are operated to convey the paper to the image forming unit 10, and the scanner unit 60, the process cartridges 70K to 70C, and the like are operated. Then, the surface of the rotating photosensitive drum 71 is uniformly positively charged by the charger 72 and then exposed to the laser beam emitted from the scanner unit 60. As a result, the surface of the photosensitive drum 71 is used for image formation. An electrostatic latent image corresponding to the data is formed.

  Next, when the developing roller 74 </ b> C is rotated, the positively charged toner carried on the developing roller 74 </ b> C is formed on the surface of the photosensitive drum 71 when it contacts the photosensitive drum 71. Supplied to the electrostatic latent image. As a result, the electrostatic latent image on the photosensitive drum 71 is visualized, and a toner image by reversal development is carried on the surface of the photosensitive drum 71.

  Thereafter, the toner image carried on the surface of the photosensitive drum 71 is transferred onto the sheet by a transfer voltage applied to the transfer rollers 73K to 73C. When the sheet on which the toner image has been transferred is conveyed to the fixing device 80, the toner image is fixed on the sheet by being heated and pressed by the heating roller 81 and the pressing roller 82. Finally, the sheet on which the image is formed is discharged to the discharge tray 5 and the image forming operation is finished.

7). Waste Toner Collection Unit When the printer 1 performs the above-described image forming operation, a part of the supplied toner may adhere to the transport belt 33 without being transferred to the paper and become unnecessary toner (waste toner). . If the image forming operation is performed while the waste toner is attached to the transport belt 33, the waste toner is retransferred onto the paper, and an unnecessary image not intended by the user is formed on the paper. Therefore, the printer 1 includes a waste toner collection unit 100 that removes toner adhering to the conveyance belt 33 below the conveyance unit 30. Details of the waste toner recovery unit 100 will be described below.

  As shown in FIG. 2, the waste toner collecting unit 100 as a single unit has a handle 103C protruding in front of a box-shaped waste toner container 101 that stores waste toner that has not been transferred to a sheet. The waste toner collecting unit 100 can be detached from the frame member of the housing 3 or attached to the frame member while holding the handle 103C.

  As shown in FIGS. 2 to 6, the waste toner container 101 includes a box-shaped container body 102 whose upper side is opened, an upper cover 103 </ b> A that covers the upper front side of the container body 102, and an upper rear side of the container body 102. The upper cover 103B is covered. The upper covers 103A and 103B are assembled to the container body 102 so as to be separable by screws or the like by fastening means.

  The upper cover 103 </ b> A is formed with an intake port 104 opened to a width substantially the same as the width of the conveyor belt 33. In the intake port 104, a cleaning roller 105, a scraping roller 106, and a peeling blade 106A are provided side by side in the front-rear direction.

  As shown in FIGS. 1 and 2, the cleaning roller 105 is a solid cylinder having a resin sponge layer formed on the outer surface side, and has a rotation axis parallel to the driving roller 31 and the driven roller 32 of the transport unit 30. It is pivotally supported so that it can rotate. The cleaning roller 105 is configured to come into contact with the transport belt 33 from below while being mounted on the frame member.

  The scraping roller 106 is a solid metal cylinder that comes into contact with the cleaning roller 105 from behind, and is rotatably supported around a rotation axis parallel to the driving roller 31, the driven roller 32, and the cleaning roller 105. Yes.

  The peeling blade 106 </ b> A is obtained by cutting a soft urethane sheet into an elongated shape, and the base side is fixed to the rear edge side of the intake port 104 in a state where the front end side is in contact with the scraping roller 106.

  As shown in FIG. 2, in the waste toner container 101, a driving force supply mechanism 190 is disposed on the left end side of the cleaning roller 105. As shown in FIGS. 3 and 4, the driving force supply mechanism 190 is a combination of a plurality of gears 191, 192, 193, 194, 195. Although not shown, the left end of the cleaning roller 105 is connected to a gear 191 constituting the driving force supply mechanism 190 so as to be integrally rotatable. Although not shown, the left end of the scraping roller 106 constitutes a driving force supply mechanism 190 and is connected to a gear 192 that meshes with the gear 191 so as to be integrally rotatable.

  In a state where the waste toner collecting unit 100 is mounted on the frame member, as shown in FIG. 4, a driving source 199 such as an electric motor provided on the frame member side and the driving force supply mechanism 190 are engaged. When the driving force of the driving source 199 is transmitted to the driving force supply mechanism 190, the gears 191, 192 and the like rotate, and the driving force of the driving source 199 is supplied to the cleaning roller 105 and the scraping roller 106. Then, as shown in FIG. 1, the cleaning roller 105 is rotationally driven in a rotation direction opposite to the circulation direction of the conveyance belt 33, so that the cleaning roller 105 rubs the waste toner adhering to the surface of the conveyance belt 33. It adheres to the surface and is removed from the conveyor belt 33. The scraping roller 106 is rotationally driven while being in contact with the surface of the cleaning roller 105 in a state where a charge (in this embodiment, a negative charge) opposite to the charge charged with the waste toner is applied, and the cleaning roller 105 The waste toner adhering to the surface is electrically adsorbed. Then, the peeling blade 106A peels off the waste toner adsorbed by the scraping roller 106 and drops it into the waste toner container 101.

  As shown in FIGS. 4 and 5, on the front side of the container main body 102, a partition wall 102 </ b> E is provided so as to extend from the right side wall 102 </ b> X to the left in a rib shape and to be interrupted before the left side wall 102 </ b> Y. Further, a rib-shaped partition wall 102F extending in the front-rear direction is provided so as to connect the left end portion of the partition wall 102E and the front side wall 102Z. A semicircular recess 148F is formed on the upper edge of the partition wall 102F.

  On the other hand, as shown in FIG. 6, on the front side of the upper cover 103A, a partition wall 103E that extends in a rib shape in the left direction from the right side wall 103X and is interrupted in front of the left side wall 103Y is erected. A rib-like partition wall 103F extending in the front-rear direction is erected so as to connect the left end portion of the partition wall 103E and the front side wall 103Z. A semicircular recess 149F is formed at the lower end edge of the partition wall 103F.

  Although illustration is omitted, when the upper cover 103A is assembled to the container body 102, the partition walls 102E and 103E are connected to the partition walls 102F and 103F, respectively, so as to partition the internal space of the waste toner container 101 in the front-rear direction and the left-right direction. It has become.

  As shown in FIGS. 3 and 4, a wide space behind the partition walls 102E and 103E among the internal space of the waste toner container 101 is a waste toner storage space 157A. On the other hand, of the internal space of the waste toner container 101, a space that is elongated to the left and right in front of the partition walls 102E and 103E is a detection space 157B for detecting the amount of waste toner accumulation. The waste toner storage space 157A and the detection space 157B are communicated with each other through a circular hole formed of the recesses 148F and 149F.

  At the bottom of the waste toner storage space 157A, a lattice member 107 and a crankshaft 108 that is rotatably supported around a rotation axis parallel to the left-right direction and connected to the front edge side of the lattice member 107 are arranged. It is installed.

  The left end of the crankshaft 108 is connected to a gear 194 constituting the driving force supply mechanism 190 so as to be integrally rotatable. When the driving force of the driving source 199 is transmitted to the driving force supply mechanism 190, the gear 194 also rotates and the driving force of the driving source 199 is also supplied to the crankshaft 108. If it does so, the crankshaft 108 will be rotationally driven and the lattice-shaped member 107 will fluctuate | variate periodically in the front-back direction in connection with it.

  The waste toner peeled off from the scraping roller 106 by the peeling blade 106A first falls to the front of the waste toner storage space 157A, and then the rear of the waste toner storage space 157A by the lattice member 107 that periodically changes in the front-rear direction. It is transferred to. When the waste toner reaches the rear end of the waste toner storage space 157A and is dammed up, it gradually starts to accumulate on the front side of the waste toner storage space 157A. Further, when the waste toner is accumulated in the waste toner storage space 157A, the waste toner flows into the detection space 157B from the circular holes (recesses 148F and 149F).

  In front of the partition walls 102E and 103E of the waste toner container 101, that is, in the detection space 157B, a rotation shaft 109A facing in a direction parallel to the left-right direction and a wing 109B spirally formed around the rotation shaft 109A are provided. A conveying screw 109 is provided. The conveying screw 109 is inserted into a circular hole (concave portion 148F, 149F) and straddles the waste toner storage space 157A and the detection space 157B.

  The left end of the rotating shaft 109A is connected to a gear 195 constituting the driving force supply mechanism 190 so as to be integrally rotatable. When the driving force of the driving source 199 is transmitted to the driving force supply mechanism 190, the gear 195 also rotates, and the driving force of the driving source 199 is also supplied to the rotating shaft 109A. Then, the conveying screw 109 is driven to rotate, and the spiral wing 109B transfers the waste toner from the left to the right. As a result, the waste toner that can no longer be stored in the waste toner storage space 157A is positively conveyed into the detection space 157B through the circular holes (recesses 148F and 149F), and from the left in the detection space 157B. Slowly deposits to the right.

  As shown in FIG. 5, on the front side of the container main body 102, on the right side of the partition wall 102F, rib-shaped partition walls 102G and 102H extending in the front-rear direction so as to connect the middle of the partition wall 102E and the front side wall 102Z, bearings A wall 102J is erected. Semicircular recesses 148G, 148H, and 148J are formed at the upper edges of the partition walls 102G and 102H and the bearing wall 102J.

  On the other hand, as shown in FIG. 6, on the front side of the upper cover 103A, on the right side of the partition wall 103F, rib-like partition walls 103G and 103H extending in the front-rear direction so as to connect the middle of the partition wall 103E and the front side wall 103Z. The bearing wall 103J is erected. Semicircular recesses 149G and 149H are formed at the upper end edges of the partition walls 103G and 103H and the bearing wall 103J.

  Although illustration is omitted, when the upper cover 103A is assembled to the container main body 102, the partition walls 102G and 102H are connected to the partition walls 103G and 103H, respectively, and the detection space 157B is divided into a plurality in the left-right direction. At this time, as shown in FIG. 7 (in FIG. 7, the upper cover 103A is not shown), a circular hole composed of recesses 148G and 149G (in FIG. 7, the recess 149G is not shown) and recesses 148H and 149H ( In FIG. 7, the rotation shaft 109 </ b> A is inserted with a gap into a circular hole made of a recess 149 </ b> H (not shown). The spiral wing 109B is formed up to the vicinity of the left side of the partition walls 102G and 103G.

  As shown in FIG. 7, the rotating shaft 109A has a pair of flange portions 109G that sandwich the circular holes (recesses 148G and 149G) in the left-right direction and a pair of flanges that sandwich the circular holes (recesses 148H and 149H) in the left-right direction. A flange portion 109H is formed.

  Although illustration is omitted, when the upper cover 103A is assembled to the container main body 102, the bearing wall 102J is connected to the bearing wall 103J to form a bearing including the recess 148J. As shown in an enlarged view in FIG. 7, the right end side of the rotation shaft 109 </ b> A is rotatably supported by the bearing including the recess 148 </ b> J.

  A cylindrical eccentric shaft portion 109 </ b> C having an axis parallel to the rotation axis of the rotation shaft 109 </ b> A protrudes from the right end portion of the rotation shaft 109 </ b> A protruding further rightward from the bearing walls 102 </ b> J and 103 </ b> J.

  Waste toner that is transported to the transport screw 109 and gradually accumulates from left to right in the detection space 157B reaches the partition walls 102G and 103G and is blocked by the partition walls 102G and 103G. And even if it is likely to flow into the right side of the partition walls 102G and 103G through the gap between the rotating shaft 109A and the circular holes (recesses 148G and 149G), the inflow is suppressed by the flange portion 109G. Even if waste toner flows into the right side of the partition walls 102G and 103G, the waste toner is blocked by the other partition walls 102H and 103H. And even if it is likely to flow into the right side of the partition walls 102H and 103H through the gap between the rotating shaft 109A and the circular holes (recesses 148H and 149H), the inflow is suppressed by the flange portion 109H. However, if waste toner is completely dammed up by the partition walls 102G and 103G and the partition walls 102H and 103H, the waste toner has no place to go, which may cause damage to the transport screw 109 and the like. For this reason, the clearance between the rotation shaft 109A, the circular holes (recesses 148G, 149G) and the circular holes (recesses 148H, 149H) is set to a size that allows the excessive waste toner to flow appropriately. The flange portions 109G and 109H can also exhibit a function of preventing the backlash of the transport screw 109 in the left-right direction and a function of supporting a reaction force received by the transport screw 109 from the transported waste toner.

  As shown in an enlarged view in FIG. 7, the rotation of the conveying screw 109 is between the partition walls 102E and 103E and the front wall 102Z of the container body 102 and the front wall 103Z of the upper cover 103A, that is, in the detection space 157B. A first displacement part 110 and a second displacement part 120 are provided adjacent to the shaft 109A.

  As shown in FIGS. 7 and 8, the first displacement part 110 includes a first connection part 113, a first passive part 111, and a first shielding part 112. The first connection portion 113 has an elongated cylindrical shaft shape that is rotatably supported around an axis parallel to the rotation shaft 109A. The first passive portion 111 has a bifurcated shape that protrudes radially outward from the right end side of the first connection portion 113 with respect to the axial center of the first connection portion 113. As shown in FIG. 7, the first passive portion 111 is assembled in a state where the eccentric shaft portion 109 </ b> C of the rotation shaft 109 </ b> A is inserted into the slit 111 </ b> A constituting the bifurcated shape. The first shielding part 112 has an elongated prismatic shape protruding from the left end side of the first connection part 113 toward the outer side in the radial direction with respect to the axis of the first connection part 113 and in the direction opposite to the first passive part 111. Is.

  As shown in FIG. 5, the front wall 102Z of the container body 102 and the front wall 103Z of the upper cover 103A are formed with recesses 102M and 103M cut away so as to avoid the first shielding part 112 protruding forward. . As shown in FIG. 7, the first shielding portion 112 protrudes further forward from the front wall 102Z of the container body 102 and the front wall 103Z of the upper cover 103A via the recesses 102M and 103M. As shown in FIGS. 9 and 10, when the eccentric shaft portion 109C rotates eccentrically with the rotation of the conveying screw 109, the first passive portion 111 and the first connecting portion 113 that engage with the eccentric shaft portion 109C are moved. Accordingly, the first shielding part 112 swings in the vertical direction.

  On the other hand, the 2nd displacement part 120 has the 2nd connection part 123, the 2nd passive part 121, and the 2nd shielding part 122, as shown in FIG.7 and FIG.8. The second connection portion 123 has an elongated cylindrical shaft shape that is rotatably supported around an axis parallel to the rotation shaft 109A. The rotation axis of the second connection portion 123 is slightly shifted forward with respect to the rotation axis of the first connection portion 113. The right end of the second connection portion 123 faces the left end of the first connection portion 113. The left end of the second connecting portion 123 extends over the partition walls 102G and 103G and extends to the right end of the spiral wing 109B. The second passive portion 121 has a flat plate shape that projects radially outward and rearward from the left end side of the second connection portion 123 with respect to the axis of the second connection portion 123. As shown in FIG. 7, the second passive portion 121 is assembled in a state in which the deposition surface 121A, which is a flat plate-shaped upward surface, is positioned below the right end portion of the spiral wing 109B. From the bottom of the container main body 102, screen-shaped regulation walls 102Q and 102R are provided so as to sandwich the deposition surface 121A in the left-right direction. The regulating walls 102Q and 102R regulate the waste toner that accumulates on the accumulation surface 121A from flowing out to the surroundings. The second shielding part 122 has an elongated column shape protruding from the right end side of the second connection part 123 to the outer side in the radial direction with respect to the axis of the second connection part 123 and in the opposite direction to the second passive part 121. Is.

  As shown in FIG. 7, the second shielding part 122 is further forward from the front wall 102Z of the container body 102 and the front wall 103Z of the upper cover 103A via the recesses 102M and 103M, like the first shielding part 112. It is in a protruding state. As shown in FIGS. 7 and 8, the second shielding part 122 has a cross-sectional shape in which a rectangular cutout 122 </ b> A extending between the right side surface and the bottom surface is formed when viewed in a cross section orthogonal to the front-rear direction. Yes. The second shielding part 122 is located above the first shielding part 112. When the second shielding part 122 comes into contact with the first shielding part 112, the first shielding part 112 fits into the notch 122A and protrudes in the left-right direction with respect to the second shielding part 122 as shown in FIG. There is no such thing.

  Since the weight of the second shielding part 122 is heavier than the weight of the second passive part 121, the second shielding part is not applied to the second passive part 121 and the second shielding part 122. The 122 side is lowered and the posture shown in FIG. 11 is held by a stopper (not shown). In this case, the second passive part 121 and the second shielding part 122 are directed substantially in the horizontal direction. On the other hand, as shown in FIG. 12, when the waste toner W is accumulated on the accumulation surface 121 </ b> A of the second passive part 121, the second shielding part 122, the second passive part 121, and the like are caused by the weight or resistance of the waste toner W. And the second passive portion 121 side is inclined downward. As a result, the second passive portion 121 is lowered and held at the lower position, and the second shielding portion 122 is raised and held at the upper position. Even when the second displacement portion 120 is held in the state shown in FIG. 12, as shown in FIG. 13, when the eccentric shaft portion 109C rotates eccentrically, the first shielding portion 112 swings up and down independently.

  In the state where the waste toner collecting unit 100 is mounted on the frame member, as shown in FIG. 4, the first shielding portion 112 and the second shielding portion 122 are optical sensors as an example of detection means provided on the frame member side. It will be in the state which protrudes toward 144. The optical sensor 144 (shown only in FIG. 4) includes a light-emitting portion 144A and a light-receiving portion 144B that face each other in the left-right direction with a space therebetween. The light emitting unit 144A is located on the left side of the first shielding unit 112 and the second shielding unit 122, and the light receiving unit 144B is located on the right side of the first shielding unit 112 and the second shielding unit 122. The optical sensor 144 is a well-known sensor that detects shielding or opening of an optical path 144C provided between the light emitting unit 144A and the light receiving unit 144B. As shown in FIGS. 9 to 13, the first shield 112 and the second shield 122 that are displaced in the vertical direction are shown in the optical path as shown in the relative positional relationship between the optical path 144 </ b> C and the first shield 112 and the second shield 122. The position which shields 144C and the position which open | release can be taken.

  As shown in FIGS. 2 and 4, the front wall 102Z of the container body 102 and the front wall 103Z of the upper cover 103A cover the first shielding part 112 and the second shielding part 122 without shielding the optical path 144C. A transparent cover 143 made of resin is attached. As shown in FIG. 5, the periphery of the transparent cover 143 has a bowl shape. The transparent cover 143 is fixed to the waste toner container 101 with a simple configuration in which the periphery of the transparent cover 143 is fitted into the fitting grooves 102N and 103N formed around the recesses 102M and 103M. . Thereby, simplification of assembly work and reduction in manufacturing cost can be realized.

8). In FIG. 14, an exposure control unit 201 controls the operation of the scanner unit 60, and a high-pressure control unit 202 operates the toner cartridge 70, that is, the photosensitive drum 71, toner development, transfer, and the like. The voltage is controlled. The panel control unit 203 controls an operation panel (not shown) set and operated by the user, and the sensor control unit 204 controls the light emitting unit 144A and the light receiving unit 144B of the optical sensor 144. The motor control unit 205 controls the electric motor of the drive source 199 provided in the printer 1.

  The ROM 206 and the RAM 207 are areas for storing information, and the CPU 208 performs arithmetic processing for controlling a control unit such as the exposure control unit 201 in accordance with a program stored in advance in the ROM 206. The timer 209 counts the time and outputs a signal indicating the time.

  As shown in FIG. 15, the sensor control unit 204 includes a light emission control circuit 210, a comparator 211, and the like. The light emission control circuit 210 controls the light emission operation of the light emitting unit 144A. The comparator 211 determines whether or not the signal level emitted when the light receiving unit 144B receives the light from the light emitting unit 144A exceeds the reference level. When the signal level exceeds the reference level, a “Low” signal is output to the CPU 208, and when the signal level is lower than the reference level, a “Hi” signal is output to the CPU 208. As described above, since the first shielding unit 112 and the second shielding unit 122 can take a position for shielding the optical path 144C and a position for opening the optical path 144C, the signal waveform output from the comparator 211 to the CPU 208, that is, the optical sensor 144. The detection result corresponds to the combination of the displacement state of the first shielding part 112 and the displacement state of the second shielding part 122.

9. Operation of First Displacement Unit, Second Displacement Unit, and Optical Sensor When the printer 1 is activated and the warm-up operation is started, or when the printer 1 is switched from the standby state to the operation state, the sensor control unit 204 detects the optical sensor. While starting the control of 144, the CPU 208 starts a determination program (steps S100 to S108 shown in FIG. 16) whose details will be described later. Further, the motor control unit 205 starts control of the drive source 199. Then, the driving force of the drive source 199 is transmitted to the conveying belt 33, and the conveying belt 33 starts to circulate and is supplied with the driving force from the driving force supply mechanism 190, and the cleaning roller 105, the scraping roller 106, the crank The shaft 108, the lattice member 107, and the conveying screw 109 also rotate or vary. As a result, the waste toner adhering to the transport belt 33 accumulates in the waste toner storage space 157A and then transported to the detection space 157B. The cleaning roller 105, the scraping roller 106, the crankshaft 108, the lattice member 107, and the conveying screw 109 correspond to waste toner transfer means.

  At this time, as shown in FIGS. 9, 10, and 13, the rotation of the conveying screw 109 causes the eccentric shaft portion 109C to rotate eccentrically, and the first passive portion 111 that engages with the eccentric shaft portion 109C swings. Then, the first shielding portion 112 also swings in the vertical direction via the first connection portion 113 to shield the optical path 114C (not shown, but the lowered position shown in FIGS. 9 and 13 and FIG. 10). And an open position (for example, a lowered position shown in FIGS. 9 and 13 and a raised position shown in FIG. 10). Here, while the eccentric shaft portion 109C makes one rotation, the first shielding portion 112 swings once in the vertical direction (one reciprocation), and the raised position shown in FIG. 10 and the lowered position shown in FIG. 9 and FIG. And take. That is, the first shielding unit 112 shields the optical path 144C twice when the eccentric shaft portion 109C rotates once.

  Here, as shown in FIG. 11, in the detection space 157B, until the waste toner W is accumulated on the accumulation surface 121A of the second passive part 121, the second passive part 121 changes the vertical displacement. Not bound by W. For this reason, the 2nd shielding part 122 integral with the 2nd passive part 121 is contacted and pushed up to the 1st shielding part 112 which moves up and down periodically, and moves up and down integrally with the 1st shielding part 112. . And the 2nd shielding part 122 takes the position (lowering position shown in FIG.9 and FIG.11) which shields the optical path 144C, and the position (for example, raising position shown in FIG.10 and FIG.12). That is, the second shielding part 122 shields the optical path 144C once when the eccentric shaft part 109C rotates once.

  As described above, when the first shielding unit 112 and the second shielding unit 122 are periodically displaced in the vertical direction to periodically shield the optical path 144C, the output signal from the optical sensor 144 is received. As shown in FIG. 17, the signal waveform output from the comparator 211 to the CPU 208 is a waveform that periodically switches between “Hi” and “Low”, and is one cycle, that is, the eccentric shaft portion 109C. The duration “T” of the “Hi” in the signal waveform during one rotation of the first rotation time is the required time T1 for one shielding when shielding the optical path 144C while the first shielding portion 112 and the second shielding portion 122 are in contact with each other. It becomes.

  On the other hand, as shown in FIG. 12, when the waste toner W is accumulated on the accumulation surface 121A of the second passive portion 121 in the detection space 157B, the second passive portion 121 and the second passive portion 121 and the second passive portion 121 depend on the weight or resistance of the waste toner W. 2 The balance with the shielding part 122 varies. The second passive portion 121 is held at the lower position, and the second shielding portion 122 is held at a position away from the first shielding portion 112 that periodically moves up and down to open the optical path 144C. . On the other hand, as shown in FIG. 13, the first shielding part 112 moves up and down independently with the rotation of the eccentric shaft part 109C.

  As described above, when only the first shielding unit 112 is periodically displaced in the vertical direction to periodically shield the optical path 144C, the comparator 211 receives the output signal from the optical sensor 144 and outputs it to the CPU 208. The signal waveform is as shown in FIG. That is, the waveform is periodically switched between “Hi” and “Low”, and the duration T of “Hi” in the signal waveform of one cycle is such that only the first shielding unit 112 has the optical path 144C. The required time T2 for one shielding when shielding is given (T2 <T1), and two “Hi” waveforms appear in one cycle.

  In addition, when a malfunction occurs in the transport screw 109, the driving force supply mechanism 190 upstream of the transport screw 109, the drive source 199, or the like during the operation of the optical sensor 144, the transport screw 109 is not rotated and the eccentric shaft The portion 109C also does not rotate eccentrically. As a result, the first passive portion 111 that engages with the eccentric shaft portion 109C also does not swing, and the first shielding portion 112 and the second shielding portion 122 also maintain the position that shields or opens the optical path 144C. . Further, when the printer 1 is started up with the waste toner collecting unit 100 removed from the housing 3, the optical path 144C remains open.

  Thus, in a state where the first shielding portion 112 and the second shielding portion 122 are stopped, or in a state where the waste toner collecting unit 100 is removed from the housing 3, the comparator 211 receives the output signal from the optical sensor 144. The signal waveform output to the CPU 208 is a waveform that remains “Hi” or “Low” as shown in FIG. 19 or 20.

10. Details of Determination Program The CPU 208 starts the determination program (steps S100 to S108) shown in FIG. Note that the determination program is repeatedly executed by the CPU 208 while the drive source 199 is activated and the drive force is supplied by the drive force supply mechanism 190, such as during the image forming operation of the printer 1. First, in step S100, a signal waveform output from the comparator 211 in response to an output signal from the optical sensor 144 is acquired.

  Next, the process proceeds to step S101, and it is determined whether or not the acquired signal waveform is a waveform that periodically changes. As shown in FIG. 19 or FIG. 20, when the acquired signal waveform is a waveform that remains “Hi” or “Low” and does not change, “No” is determined in step S101, and the process proceeds to step S102. Then, in step S102, it is determined that “the conveying screw 109 or the driving force supply mechanism 190 on the upstream side of the conveying screw 109 is not normal”, the CPU 208 is notified of this, and the process is terminated. As a result, the CPU 208 assumes various troubles such as breakage of the conveying screw 109, damage to the driving force supply mechanism 190 and the like on the upstream side of the conveying screw 109, poor supply of driving power, or no mounting of the waste toner collecting unit 100. Troubleshooting and warnings to users. In this case, the printer 1 stops the image forming operation until a predetermined countermeasure is taken for the warning.

  On the other hand, when the acquired signal waveform is a waveform that periodically switches between “Hi” and “Low”, as shown in FIG. 17 or FIG. 18, “Yes” is set in step S 101, and the process proceeds to step S 103. . Then, “Hi” duration T in one cycle is extracted from the output signal waveform.

  Next, the process proceeds to step S104, where it is determined whether the “Hi” duration T in one cycle is greater than a threshold G. Here, in the present embodiment, the threshold G is set to a value approximately in the middle between the required time T1 and the required time T2 (T2 <G <T1). As shown in FIG. 17, when the acquired signal waveform is “Hi” duration T = required time T <b> 1 in one cycle, “Yes” is obtained in step S <b> 104, and the waste toner W is stored in the second passive unit 121. It is determined that the material is not deposited on the deposition surface 121A, and the process is terminated. And the said process is repeated from step S100. In this embodiment, the state in which the waste toner W is accumulated on the accumulation surface 121A of the second passive unit 121 is referred to as “near full” which means a state close to “full” meaning full. .

  On the other hand, as shown in FIG. 18, when the acquired signal waveform is “Hi” duration T = required time T2 in one cycle, “No” is determined in step S104, and the process proceeds to step S105. In step S105, it is determined that the waste toner W has accumulated on the accumulation surface 121A of the second passive portion 121, that is, the waste toner is “near full”, and the CPU 208 is notified of this. In response to this, for example, the CPU 208 notifies the user that “the replacement timing of the waste toner collection unit 100 is approaching”.

  Next, the process proceeds to step S106, and measurement of a timer for determining that the waste toner is “full” is started. Specifically, the CPU 208 controls the timer 209 to measure the time until the operation time of the printer 1 after determining “near full” reaches the set time.

  Next, the process proceeds to step S107, and when the waste toner “full” determination timer reaches the set time (S107: Yes), the process proceeds to step S108. Further, until the waste toner “full” determination timer reaches the set time (S107: NO), this processing is once ended, and the above processing is repeated from step S100. Thereby, even when the waste toner is in the “near full” state, the acquisition of the signal waveform can be continued, and the detection of whether or not the drive supply mechanism and the conveying screw are operating normally can be continued. Once the waste toner is notified as “near full” in step S105, and the measurement by the waste toner “full” determination timer is started in step S106, the internal processing in steps S105 and S106 is not performed, and S107 is performed. Move on to processing.

  In step S108, it is determined that the waste toner is “full”, the CPU 208 is notified of this, and the process is terminated. In response to this, for example, the CPU 208 notifies the user that “please replace the waste toner collecting unit 100 immediately”. Also in this case, the printer 1 stops the image forming operation until a predetermined countermeasure is taken for the notification.

<Effect>
The printer 1 according to the embodiment includes a waste toner container 101 having the above-described configuration, a driving force supply mechanism 190, a conveyance screw 109 that constitutes waste toner transfer units 105 to 109, a first displacement unit 110, and a second displacement. Unit 120, optical sensor 144, and determination means S100 to S108.

  The first displacement unit 110 includes a first shielding unit 112 that can take a position for shielding the optical path 144C and a position for opening the optical path 144C by the displacement, and the second displacement unit 120 has a waste toner that has reached a specific accumulation state. When there is no waste toner W (when the waste toner W is not deposited on the deposition surface 121A), the first shield 112 can be displaced integrally to take a position for shielding the optical path 144C and a position for opening it. When the toner reaches a specific accumulation state (when waste toner W accumulates on the accumulation surface 121A), the second shielding portion 122 is moved away from the first shielding portion 112 and displaced to a position where the optical path 144C is opened. .

  According to this printer 1, the detection result corresponding to the combination of the displacement state of the first displacement unit 110 and the displacement state of the second displacement unit 120 is output by the optical sensor 144, and based on the detection result, determination means S100 to S108. Thus, two types of determinations (abnormality of the conveying screw 109 constituting the waste toner transfer means, the driving force supply mechanism 190 on the upstream side thereof, the toner accumulation state) can be distinguished.

  More specifically, when there is no abnormality in the conveying screw 109 or its upstream side, the first shielding part 112 and the second shielding part 122 periodically shield the optical path 144C, so that the optical sensor 144 has periodic fluctuations. The detection result (for example, the signal waveform shown in FIG. 17 or FIG. 18) is output. On the other hand, if an abnormality such as a failure occurs on the conveying screw 109 or its upstream side and the conveying screw 109 stops, the first shielding portion 112 and the second shielding portion 122 remain shielding or opening the optical path 144C. The sensor 144 outputs a detection result (for example, a signal waveform shown in FIG. 19 or FIG. 20) having no periodic fluctuation. As a result, the determination means S100 to S108 can immediately determine that there is an abnormality in the conveying screw 109 or its upstream side by steps S101 and S102.

  In addition, the second shielding unit 122 and the first shielding unit 112 are periodically used until the waste toner reaches a specific accumulation state (a state in which the waste toner W is accumulated on the accumulation surface 121A) in the waste toner container 101. The optical path 144C is shielded. On the other hand, when the waste toner reaches a specific accumulation state, the second shielding unit 122 moves away from the first shielding unit 112 to a position where the optical path 144C is opened, and only the first shielding unit 112 is periodically. The optical path 144C is shielded. For this reason, the optical sensor 144 outputs a detection result (signal waveform shown in FIG. 17 or FIG. 18) having a periodic variation and having different “Hi” durations in one cycle. As a result, the determination means S100 to S108 can immediately determine that the waste toner has become “near full” in steps S103 to S105. That is, according to the prior art, two detection means are necessary to make such two types of determination. According to the printer 1, the two types of determination can be made distinguishable by one optical sensor 144. .

  Therefore, according to the printer 1, the apparatus configuration can be simplified, and as a result, the manufacturing cost can be reduced.

  The second displacement part 120 includes a second passive part 121, a second shielding part 122, and a second connection part 123. The second passive part 121 is a second shielding part until the waste toner W is deposited. The vertical displacement associated with the displacement of the portion 122 is not constrained. On the other hand, when the waste toner W is accumulated, it is formed to be held at the lower position. The second shielding part 122 abuts against the first shielding part 112 from above by its own weight while the second passive part 121 is not restrained in the vertical displacement associated with the displacement of the second shielding part 122. Thus, it is displaced in the vertical direction integrally with the first shielding part 112. On the other hand, when the second passive part 121 is held at the lower position, the second shielding part 122 is formed to be held at a position away from the first shielding part 112 upward. As described above, the printer 1 can use the fact that the balance between the second shielding unit 122 and the second passive unit 121 changes due to the waste toner accumulated on the second passive unit 121, so that the apparatus configuration is further improved. It can be simplified.

  Furthermore, when viewed in a cross section orthogonal to the front-rear direction, which is the direction in which the first shielding portion 112 and the second shielding portion 122 project, that is, in a cross section in the direction along the optical path 144C, A notch 122A in which the first shielding part 112 is accommodated is formed. The first shielding portion 112 has a cross-sectional shape that does not protrude in a direction parallel to the optical path 144C with respect to the second shielding portion 122 in a state of being accommodated in the notch 122A. For this reason, since the width | variety of the 1st, 2nd shielding parts 112 and 122 can be narrowed, the light emission part 144A and the light-receiving part 144B can be made to approach. As a result, it is possible to reduce the size of the optical sensor 144 and hence the printer 1.

  The second connecting portion 123 extends long along the conveying screw 109, and the second passive portion 121 is disposed upstream in the direction in which the waste toner is transferred. The first shielding unit 112 and the second shielding unit 122 are disposed away from the second passive unit 121 on the downstream side in the direction in which the waste toner is transferred. For this reason, even when the waste toner is accumulated on the second passive portion 121, it is possible to make it difficult for the waste toner to reach the first shielding portion 112 and the second shielding portion 122, so that the detection accuracy of the optical sensor 144 is reduced. Can be suppressed.

  Further, a detection space 157B is provided between the second passive part 121 and the first shielding part 112 and the second shielding part 122. The space on the second passive part 121 side and the first and second shielding parts 112, 122 are also provided. Partition walls 102G and 103G and a partition wall 102H and 103H that are partitioned into a side space are provided. For this reason, even when waste toner accumulates on the second passive portion 121, the waste toner reaches the first shielding portion 112 and the second shielding portion 122 by the partition walls 102G and 103G and the partition walls 102H and 103H. Therefore, it is possible to further prevent a decrease in detection accuracy of the optical sensor 144.

  Further, only the first shielding unit 112 shields the optical path 144C with respect to the required time T1 for one shielding when the optical path 144C is shielded while the first shielding unit 112 and the second shielding unit 122 are in contact with each other. The size of the first shielding part 112 and the second shielding part 122 facing the optical path 144C is set so that the required time T2 for one shielding is shortened. For this reason, the optical sensor 144 is easily distinguishable between the case where the first and second shielding portions 112 and 122 are periodically displaced and the case where only the first shielding portion 112 is periodically displaced. The detection result with is output. Therefore, the determination in step S104 in determination means S100 to S108 can be performed more accurately.

  Further, the waste toner container 101, the driving force supply mechanism 190, the waste toner transfer means 105 to 109, the first displacement portion 110 and the second displacement portion 120 are provided so as to be detachable from the frame member of the housing 3. The unit 100 is configured. The optical sensor 144, the CPU 208 and the ROM 206 that execute the determination units S100 to S108 are provided on the housing 3 side. In this configuration, even when the waste toner recovery unit 100 is removed, the determination means S100 to S108 determine that there is an abnormality in the conveying screw 109 or its upstream side, so the waste toner recovery unit 100 is attached. The trouble that the printer 1 operates without being present can be prevented.

  While the present invention has been described with reference to the embodiments, it is needless to say that the present invention is not limited to the above-described embodiments and can be appropriately modified and applied without departing from the spirit thereof.

  For example, you may arrange | position the 1st displacement part 110 and the 2nd displacement part 120 adjacent to the rear-end edge of the grid | lattice-like member 107. FIG. In this case, the first passive portion 111 engages with the rear end edge of the lattice-like member 107 and swings periodically. Further, when the waste toner is accumulated up to the rear end edge of the grid member 107, the second passive portion is displaced correspondingly. Even with such a configuration, the effects of the present invention can be achieved.

  Further, the “determination program” shown in FIG. 16 is configured to be executed only for a predetermined period at the start of the image forming operation, or to be periodically executed during the driving period of the driving force supply mechanism 190. However, the present invention is not limited to the method of continuously executing as in the present embodiment.

  The present invention is applicable to an image forming apparatus.

1. Image forming apparatus (printer)
W ... waste toner 101 ... waste toner container 199 ... drive source 190 ... drive force supply mechanism 105, 106, 107, 108, 109 ... waste toner transfer means (105 ... cleaning roller, 106 ... scraping roller, 107 ... lattice-like member 108, crankshaft, 109, conveying screw)
DESCRIPTION OF SYMBOLS 110 ... 1st displacement part 120 ... 2nd displacement part 144 ... Detection means (optical sensor)
144A ... Light emitting unit 144B ... Light receiving unit S100 to S108 ... Judgment means 111 ... First passive unit 112 ... First shielding unit 113 ... First connecting unit 121 ... Second passive unit 122 ... Second shielding unit 123 ... Second connecting unit 122A: Notches for accommodating the first shielding part 157A, 157B: Internal space of the waste toner container (157A: Waste toner storage space, 157B: Detection space)
102G, 103G, 102H, 103H ... partition wall T ... duration of one-time shielding of the optical path in the detection result T1 ... required for one shielding when shielding the optical path while the first and second shielding parts are in contact with each other Time T2: Time required for one shielding time when only the first shielding part shields the optical path 3 ... Housing 100 ... Waste toner recovery unit

Claims (9)

An image forming apparatus that forms an image on the recording medium by transferring a toner image to the recording medium,
A waste toner container for storing waste toner that has not been transferred to the recording medium;
A driving force supply mechanism for supplying a driving force of a driving source;
Waste toner transfer means that is driven by a driving force supplied by the driving force supply mechanism and transfers the waste toner from the outside to the inside of the waste toner container and / or from one to the other inside the waste toner container; ,
A first displacement portion that is periodically displaced in conjunction with the waste toner transfer means;
A second displacement portion that is displaced according to a state of accumulation of the waste toner in the waste toner container;
Detection means for outputting a detection result corresponding to a combination of a displacement state of the first displacement portion and a displacement state of the second displacement portion;
Based on the detection result, it is distinguished whether there is an abnormality in the driving force supply mechanism or the waste toner transfer means and whether the waste toner has reached a specific accumulation state in the waste toner container. An image forming apparatus comprising: a determination unit configured to perform determination as possible. The detection means has a light emitting part and a light receiving part facing each other with a gap, and detects shielding or opening of an optical path provided between the light emitting part and the light receiving part,
The first displacement part has a first shielding part that can take a position for shielding the optical path by a displacement and a position for opening the light path,
The second displacing portion is displaced integrally with the first shielding portion when the waste toner has not reached the specific accumulation state, and takes a position where the light path is shielded and a position where it is opened. 2. The image forming apparatus according to claim 1, further comprising: a second shielding portion that moves away from the first shielding portion to a position that opens the optical path when the waste toner reaches the specific accumulation state. apparatus. The first displacement part is engaged with the waste toner transfer means and receives a driving force, and periodically and vertically in conjunction with the waste toner transfer means via the first passive part. The first shielding part that is displaced and shields or opens the optical path, and the first connection part that integrally connects the first passive part and the first shielding part,
The second displacement portion includes a second passive portion provided at a position in contact with waste toner, the second shielding portion, and a second connection portion that integrally connects the second passive portion and the second shielding portion. And consist of
The second passive portion is not restrained in the vertical displacement due to the displacement of the second shielding portion until the waste toner is accumulated, but is held at a lower position when the waste toner is accumulated. Formed,
The second shielding part is in contact with the first shielding part from above by its own weight while the second passive part is not restrained in the vertical displacement associated with the displacement of the second shielding part, While being displaced up and down integrally with the first shielding part, when the second passive part is held at the lower position, it is held at a position away from the first shielding part. The image forming apparatus according to claim 2, wherein the image forming apparatus is formed. As seen in a cross section in the direction along the optical path, a notch in which the first shielding part is accommodated is formed across one side surface and the lower surface of the second shielding part,
4. The image forming apparatus according to claim 3, wherein the first shielding part has a cross-sectional shape that does not protrude in a direction parallel to the optical path with respect to the second shielding part in a state of being accommodated in the notch. The second connection part extends from the second passive part toward the downstream side in the direction in which the waste toner is transferred,
The said 1st shielding part and the said 2nd shielding part are arrange | positioned apart with respect to the said 2nd passive part in the downstream of the direction in which the said waste toner is conveyed. The image forming apparatus described.   Between the second passive part, the first shielding part, and the second shielding part, an internal space of the waste toner container is formed between the space on the second passive part side and the first and second shielding part sides. The image forming apparatus according to claim 5, further comprising a partition wall that divides the space.   With respect to the time required for one shielding when the optical path is shielded while the first shielding part and the second shielding part are in contact with each other, the shielding is performed once when only the first shielding part shields the optical path. 7. The image forming apparatus according to claim 2, wherein sizes of the first shielding portion and the second shielding portion facing the optical path are set so as to shorten a required time. The determination means determines that “the drive force supply mechanism or the waste toner transfer means is abnormal” when the detection result is not periodically fluctuated;
When the detection result has periodic fluctuations, it is determined that “the driving force supply mechanism and the waste toner transfer unit are not abnormal”, and the duration of the light path shielding once in the detection result. Is longer than the threshold value, it is determined that “the waste toner has not reached a specific accumulation state”, while if the duration of one blocking of the optical path in the detection result is equal to or less than the threshold value, “Waste toner is specified. The image forming apparatus according to claim 7, wherein the image forming apparatus determines that the storage state has been reached. A housing,
The waste toner container, the driving force supply mechanism, the waste toner transfer means, the first displacement portion, and the second displacement portion constitute a waste toner collection unit that is detachably attached to the housing.
The image forming apparatus according to claim 1, wherein the detection unit and the determination unit are provided on the housing side.

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