JP6683177B2 - Waste developer recovery device and image forming apparatus including the same - Google Patents

Description

  The present invention relates to a waste developer collecting device that collects and stores a used developer from an image forming unit, and an electrophotographic image forming apparatus including the waste developer collecting device.

  Generally, an electrophotographic image forming apparatus includes a waste developer collecting device that collects and stores a used developer (hereinafter referred to as “waste developer”) used in an image forming unit. The waste developer collecting device includes a developer container that stores the waste developer, and a container mounting portion that detachably mounts the developer container.

  The waste developer collecting device includes a full detection sensor such as a weight sensor for detecting that the developer container is full when the developer container is full (see Patent Document 1). When the fullness detection sensor detects that the image forming apparatus is full, the image forming apparatus notifies the user to that effect. By confirming the notification, the user can know that the developer container is full and the replacement timing of the developer container. As the fullness detection sensor, for example, a spring that supports the load of the bottle mounting portion mounted on the container mounting portion, and a detection that detects that the developer container has descended to a predetermined height due to its weight A device including a sensor is known.

  However, if the full-state detection sensor fails, the user will not be able to keep track of it even when the developer container is full. On the other hand, if the full detection sensor fails and the developer flow path from the developer container to the image forming unit is filled with the waste developer, not only the image formation by the image forming unit is hindered. However, there is a problem in that the waste developer flowing back to the image forming unit causes the image forming unit to malfunction. Therefore, the conventional waste developer recovery device is provided with a developer detection sensor for detecting the presence or absence of the waste developer filled in the developer flow path even when the full detection sensor fails. There is. As the developer detection sensor, a piezoelectric sensor having an input surface to which pressure is input is used. The waste developer collecting device is provided with the piezoelectric sensor in a state where the input surface is exposed to the developer flow path.

JP, 2011-209621, A

  However, when the input surface is exposed in the developer flow path, the waste developer may adhere to the input surface and cause the piezoelectric sensor to malfunction.

  An object of the present invention is to provide a waste developer recovery device that can reliably detect the presence or absence of waste developer in the developer flow path, and an image forming apparatus including the waste developer recovery device.

  A waste developer recovery device according to one aspect of the present invention includes a developer container, a guide flow path portion, a developer detection sensor, a first magnet member, a cleaning member, and a second magnet member. . The developer container has an opening through which the waste developer discharged from the image forming unit can flow. The guide flow path portion is provided on the upper side of the opening portion and has a tubular shape that guides the waste developer from the image forming portion toward the opening portion. The developer detection sensor is provided in the guide flow passage portion such that a pressure detection surface is exposed to the inside of the guide flow passage portion through an insertion opening formed in an outer peripheral wall of the guide flow passage portion. The presence or absence of the waste developer inside the guide flow path portion is detected based on the pressure applied to the surface. The first magnet member is provided inside the guide flow path portion so as to face the pressure detection surface, and the first magnetic pole surface having a predetermined polarity covers the pressure detection surface and has the guide flow path portion. Is directed to the inside of the. The cleaning member is provided inside the guide flow path portion so as to be vertically movable, and comes into contact with and removes the developer attached to the first magnetic pole surface. The second magnet member is attached to the cleaning member with a predetermined gap from the first magnet member, and the second magnetic pole surface having the same polarity as the first magnetic pole surface is the first magnetic pole surface. Are arranged so as to face each other.

  An image forming apparatus according to another aspect of the present invention includes an image forming unit that forms an image on a transfer medium using a developer, and the waste developer collecting device.

  According to the present invention, it is possible to reliably detect the presence or absence of waste developer in the developer flow path.

FIG. 1 is a view showing the arrangement of an image forming apparatus according to the first embodiment of the present invention. FIG. 2 is a perspective view of a developer bottle included in the image forming apparatus according to the first embodiment of the present invention. FIG. 3 is a perspective view of the waste developer collecting portion according to the first embodiment of the present invention. FIG. 4 is a diagram showing the configuration of the waste developer recovery unit according to the first embodiment of the present invention. FIG. 5 is an enlarged view showing the configurations of the receiving section and the piezoelectric sensor of the waste developer collecting section according to the first embodiment of the present invention. FIG. 6 is a diagram showing a waste developer transporting mechanism of the waste developer collecting section according to the first embodiment. FIG. 7 is an enlarged view showing the configurations of the receiving portion and the piezoelectric sensor of the waste developer collecting portion according to the second embodiment of the present invention. FIGS. 8A to 8C are schematic diagrams showing the configurations of other cushioning members having different shapes. FIG. 9 is an enlarged view showing the cross-sectional structure of the waste developer collecting portion according to the third embodiment of the present invention. FIG. 10 is a perspective view showing a cleaning member of the waste developer collecting portion according to the third embodiment of the present invention. FIG. 11 is a diagram showing a positional relationship between the magnet sheet and the magnet plate of the waste developer collecting portion according to the third embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. The embodiments described below are merely examples embodying the present invention and do not limit the technical scope of the present invention.

[First Embodiment]
First, a first embodiment of the present invention will be described.

[Image forming apparatus 10]
The image forming apparatus 10 according to the first exemplary embodiment of the present invention is an apparatus that forms an image on a sheet by an electrophotographic method. The sheet is a sheet-shaped image forming medium (transfer target medium) such as a sheet and an envelope.

  The image forming apparatus 10 includes a sheet supplying unit 2, a sheet conveying unit 3, an image forming unit 40, an optical scanning unit 46, a fixing unit 49, a toner replenishing unit 400, and a waste developer collecting unit 6 (waste developer) inside the main body 1. An example of a recovery device) is provided.

  The image forming unit 40 executes an image forming process for forming an image on a sheet using the developer 9. The image forming unit 40 includes the image forming unit 4 and other devices related to development and conveyance of the developer 9. The developer 9 is a two-component developer containing the toner 9a and the carrier 9b. The carrier 9b is a granular material having magnetism. More specifically, the carrier 9b is a granular material of a soft magnetic material. For example, when the carrier 9b is placed close to a magnet and placed in a magnetic field (magnetic field) by the magnet, the carrier 9b itself is magnetically polarized and becomes a magnet. It is something that magnetizes.

  The image forming apparatus 10 shown in FIG. 1 is a so-called tandem type color image forming apparatus, and is, for example, a color printer. Therefore, the image forming unit 40 includes a plurality of image forming units 4 corresponding to the toners 9a of a plurality of colors, an intermediate transfer belt 47, a secondary transfer device 48, and a belt cleaning unit 470. Further, the toner replenishing section 400 is also provided for each color of the toner 9a.

  Each image forming unit 4 includes a photoconductor 41, a charging unit 42, a developing unit 43, a primary transfer unit 44, a drum cleaning unit 45, and the like. In the image forming unit 4 of the image forming unit 40, the developing unit 43 forms a toner image on the outer peripheral surface of the photoconductor 41. Further, in the image forming unit 40, the primary transfer unit 44 transfers the toner image on the photoconductor 41 to the intermediate transfer belt 47.

  The sheet supply unit 2 sends the sheet to the sheet conveyance path 30, and the sheet conveyance unit 3 conveys the sheet along the sheet conveyance path 30. The intermediate transfer belt 47 is an endless belt-shaped member and rotates while being stretched over two rollers.

  In each of the image forming units 4, the drum-shaped photoconductor 41 rotates, and the charging unit 42 uniformly charges the surface of the photoconductor 41. The optical scanning unit 46 writes an electrostatic latent image on the surface of the photoconductor 41 by scanning the laser light.

  The developing unit 43 uses the developer 9 containing the carrier 9b held in advance and the unused toner 9a supplied from the toner replenishing unit 400 to form the electrostatic latent image as an image of the toner 9a (toner image). To develop. As a result, an image of the toner 9a is formed on the surface of the photoconductor 41.

  The primary transfer portion 44 transfers the image of the toner 9 a on the surface of the photoconductor 41 to the intermediate transfer belt 47. Then, the image of the toner 9 a is transferred from each of the plurality of photoconductors 41 to the intermediate transfer belt 47. As a result, a color image in which the images of the toners 9a of the respective colors are superimposed is formed on the intermediate transfer belt 47. The drum cleaning unit 45 removes the toner 9a remaining on the surface of the photoconductor 41.

  The photoconductor 41 and the intermediate transfer belt 47 are an example of an image carrier that carries the image of the toner 9a.

  The secondary transfer device 48 transfers the color image formed on the intermediate transfer belt 47 onto the sheet. The belt cleaning unit 470 removes the toner 9a remaining on the intermediate transfer belt 47. The fixing unit 49 fixes the color image on the sheet by heating.

  The toner 9a removed from the photoconductor 41 and the intermediate transfer belt 47 by the drum cleaning unit 45 and the belt cleaning unit 470 is conveyed to the waste developer collecting unit 6, and the developer bottle 5 (developer) of the waste developer collecting unit 6 is conveyed. It is housed in an example of a container). The developer bottle 5 is detachably attached to the bottle attaching portion 60 of the waste developer collecting portion 6.

  Further, the toner 9 a floating in the developing unit 43 and a part of the carrier 9 b deteriorated in the developing unit 43 are also transported to the waste developer collecting unit 6 and stored in the developer bottle 5.

  In the following description, the used developer 9 collected from the drum cleaning unit 45, the belt cleaning unit 470 and the developing unit 43 to the developer bottle 5 is referred to as a waste developer 90.

  The waste developer 90 is the waste toner 90a that is the toner 9a collected from the drum cleaning unit 45, the belt cleaning unit 470, and the developing unit 43, and the waste carrier 9b that is the carrier 9b that is collected from the developing unit 43 to the developer bottle 5. 90b and.

  In the present exemplary embodiment, the plurality of image forming units 4, the intermediate transfer belt 47, the secondary transfer device 48, and the belt cleaning unit 470 each form a part of the image forming unit 40. In the image forming apparatus 10, the waste developer 90 collected from the image forming unit 40 is contained in the developer bottle 5.

  Further, the image forming apparatus 10 includes a control unit 8 that performs various calculations and controls electric devices in the image forming apparatus 10.

[Waste developer collecting section 6]
The waste developer collecting section 6 includes a developer bottle 5, a bottle mounting section 60, and a support frame 66.

  As shown in FIG. 2, the developer bottle 5 is a long bottle-shaped container having a hollow inside. The developer bottle 5 has an opening 50 (an example of an opening) that is an inlet of the waste developer 90. The opening 50 is formed in a size, shape, and position that allows the waste developer 90 discharged from the image forming unit 40 to flow in. In this embodiment, the opening 50 is formed at the first end 51 on one side in the longitudinal direction of the developer bottle 5. The second end 52 opposite to the first end 51 is closed.

  The developer bottle 5 is mounted on the bottle mounting portion 60 in a state where the longitudinal direction thereof is the horizontal direction. In the following description, the direction in which the developer bottle 5 is inserted into the bottle mounting portion 60 with the opening 50 at the top is referred to as a bottle insertion direction D1 (see FIGS. 2 and 3).

  The developer bottle 5 has a spiral convex portion 54 spirally formed around a center line L1 along the longitudinal direction thereof. The spiral convex portion 54 is a portion that spirally protrudes toward the inner surface side of the developer bottle 5. The spiral convex portion 54 is a spiral concave portion when viewed from the outside of the developer bottle 5.

  The bottle mounting portion 60 is a storage case that is long in the bottle insertion direction D1 and stores the developer bottle 5. The bottle mounting portion 60 includes a bottle receiving portion 61 that holds the lower side of the developer bottle 5, and a bottle cover 62 that covers the upper side of the developer bottle 5. The bottle mounting portion 60 is configured by vertically assembling a bottle receiving portion 61 and a bottle cover 62. The bottle receiving portion 61 is a support base that supports the outer peripheral portion of the lower half of the developer bottle 5. The developer bottle 5 is rotatably supported by the bottle mounting portion 60. The bottle receiving portion 61 and the bottle cover 62 are resin molded products made of synthetic resin, for example. In addition, in FIG. 4, the bottle cover 62 is indicated by a two-dot chain line.

  The bottle receiving portion 61 supports the outer peripheral surface 53 of the developer bottle 5 from below. The bottle cover 62 covers the developer bottle 5 from the upper side. The bottle mounting portion 60 has a mounting space 600 (see FIG. 4) inside which the developer bottle 5 is inserted along the longitudinal direction thereof. The mounting space 600 is a space in which the developer bottle 5 is mounted.

  The support frame 66 is provided on the main body 1. The support frame 66 supports the bottom portion of the bottle receiving portion 61 of the bottle mounting portion 60, and has a bottom plate 66A and side plates 66B. The support frame 66 is formed of, for example, a sheet metal member. The support frame 66 is formed in a plate shape that is long in the longitudinal direction of the bottle mounting portion 60.

  The developer bottle 5 is mounted in the bottle mounting portion 60 by inserting the developer bottle 5 into the mounting space 600 from the insertion opening 60A of the bottle mounting portion 60 along the bottle insertion direction D1 with the opening 50 at the top. With the developer bottle 5 mounted in the bottle mounting portion 60, the opening 50 is arranged in the carry-in relay portion 64. Further, the developer bottle 5 is removed from the bottle mounting portion 60 by being pulled out from the mounting space 600 in the direction opposite to the bottle insertion direction D1. A part of the exterior of the main body 1 (see FIG. 1) forms an open / close cover (not shown) that is opened when the developer bottle 5 is attached and detached. When the opening / closing cover is opened, the insertion opening 60A is opened.

  As shown in FIG. 3, the waste developer collecting section 6 includes a receiving section 63, a carry-in relay section 64, a drive transmitting section 65, a piezoelectric sensor 80 (see FIG. 5, an example of a developer detecting sensor), and a waste developing section. The agent transport mechanism 100 (see FIG. 6) is further provided.

  The carry-in relay section 64 is a section in which a relay transport path (not shown) is formed. The carry-in relay section 64 is provided at the end of the bottle mounting section 60 on the bottle insertion direction D1 side. The relay conveyance path is a conveyance path for the waste developer 90 that connects the receiving portion 63 and the opening 50 of the developer bottle 5. The waste developer 90 is carried into the developer bottle 5 from the opening 50 via the relay conveyance path in the carry-in relay section 64 from the receiving section 63. The carry-in relay section 64 is a resin molded product made of synthetic resin. The carry-in relay section 64 may be formed integrally with the bottle mounting section 60, or may be configured as a separate member.

  The receiving portion 63 is provided above the carry-in relay portion 64, in other words, above the opening 50 of the developer bottle 5. The receiving portion 63 receives the waste developer 90 falling from the waste developer transport mechanism 100 (see FIG. 6) and guides it to the opening 50 via the carry-in relay portion 64. The waste developer transport mechanism 100 is led out. It has a bellows tube 68 whose upper end is connected to the tube 107, and a receiving portion 67 (an example of a guide flow path section) whose lower end is connected to the bellows tube 68.

  The receiving portion 67 is a flow path for guiding the waste developer 90 falling from the waste developer transport mechanism 100 downward, and is formed in a hollow tubular shape. The internal space 67A (see FIG. 5) of the receiving portion 67 is formed in a straight shape in the downward direction in which the waste developer 90 is guided. The waste developer 90 guided downward from the image forming unit 40 (see FIG. 1) through the bellows pipe 68 is guided to the inside of the carry-in relay unit 64 through the internal space 67A (see FIG. 5) of the receiving unit 67. After that, it flows into the opening 50 of the developer bottle 5.

  The waste developer transport mechanism 100 is a mechanism that transports the waste developer 90 from each of the drum cleaning unit 45, the belt cleaning unit 470, and the developing unit 43 to the receiving unit 63. As shown in FIG. 6, the waste developer transport mechanism 100 discharges the waste developer 90 discharged and collected from each of the drum cleaning section 45, the belt cleaning section 470 and the developing section 43 toward the receiving section 63 side. A discharge path 101 that guides the waste developer 90 in the discharge path 101 and a spiral conveying member 103 that conveys the waste developer 90 in the discharge path 101 in the discharge direction are provided. A conveyance member 103 is rotatably provided inside the discharge path 101. The transport member 103 is a member that is long in the discharging direction, and has a rotating shaft 104 and a spiral blade 105 integrally mounted around the rotating shaft 104. The rotating shaft 104 is rotatably supported by support walls (not shown) provided at both ends of the discharge path 101 in the longitudinal direction. An input gear (not shown) to which the rotational drive force is input is attached to one end of the rotary shaft 104, and the rotational drive force transmitted from a drive source such as a motor is input to the input gear. The transport member 103 is rotated by the input of the rotational driving force, whereby the waste developer 90 in the discharge path 101 is transported in the discharge direction. A discharge port 106 for discharging the waste developer 90 downward is formed at the end of the bottom surface of the discharge path 101 in the discharge direction. The waste developer transport mechanism 100 further includes a tubular lead-out pipe 107 extending downward from the discharge port 106. The bellows tube 68 is connected to the outlet tube 107. The waste developer 90 transported to the discharge port 106 by the transport member 103 is guided to the carry-in relay section 64 from the discharge port 106 through the outlet pipe 107 and the bellows pipe 68.

  The drive transmission unit 65 is a gear mechanism that transmits the rotational force of a motor (not shown) to the developer bottle 5. The developer bottle 5 mounted on the bottle mounting portion 60 receives the rotational force from the drive transmission portion 65 and rotates around the center line L1 in the predetermined rotation direction D2.

  By rotating the developer bottle 5 in the rotation direction D2, the waste developer 90 moves in a direction away from the opening 50 in the horizontally placed developer bottle 5. As a result, the waste developer 90 is prevented from being unevenly accumulated on the opening 50 side. Further, the uneven distribution of the waste toner 90a and the waste carrier 90b in the developer bottle 5 is alleviated.

  The bottle mounting portion 60 is supported by a support frame 66 which is a part of the main body 1 so as to be vertically movable (movable up and down). The support frame 66 is provided with a rotation shaft 661 that supports the bottle mounting portion 60 so as to be vertically movable. The rotation shaft 661 is provided on the support frame 66 at a position near the first end 51 of the developer bottle 5. The bottle mounting portion 60 is supported by a support frame 66 so as to be rotatable around a rotation shaft 661. As a result, the bottle mounting portion 60 can move up and down on the side opposite to the bottle insertion direction D1.

  As shown in FIG. 4, the waste developer recovery unit 6 further includes a full-state detection mechanism 70 that detects whether the inside of the developer bottle 5 is full of the waste developer 90. As the weight of the waste developer 90 in the developer bottle 5 increases, the bottle mounting portion 60 is displaced downward about the rotation shaft 661. The fullness detection mechanism 70 stores the amount of the waste developer 90 considered to be full in the developer bottle 5 and when the downward displacement amount of the bottle mounting portion 60 exceeds a preset reference value. It is detected that the inside of the developer bottle 5 is filled with the waste developer 90.

  The fullness detection mechanism 70 specifically includes a spring 71, an interlocking piece 72, and an optical sensor 73. Both the interlocking piece 72 and the optical sensor 73 are provided on the upper surface of the bottom plate 66A.

  The spring 71 is, for example, a coil spring. The spring 71 applies an elastic force upward to the bottle mounting portion 60. The spring 71 is interposed between the bottom portion of the bottle receiving portion 61 and the bottom plate 66A of the support frame 66. The spring 71 is arranged near the end of the bottle mounting portion 60 on the side opposite to the bottle insertion direction D1. The lower end of the spring 71 is attached to the bottom plate 66A, and the upper end thereof is attached to the bottle receiving portion 61. Accordingly, the bottle mounting portion 60 is supported on the bottom plate 66A by the elastic force of the spring 71 while the developer bottle 5 is accommodated in the mounting space 600. Therefore, when the waste developer 90 flows into the developer bottle 5 and the storage amount of the waste developer 90 increases, the spring 71 contracts according to the increased weight, and the bottle mounting portion 60 moves in the gravity direction (downward). Will be displaced to.

  The interlocking piece 72 moves in the same gravity direction as the bottle mounting portion 60 is displaced in the gravity direction (downward) together with the developer bottle 5. Specifically, the interlocking piece 72 is an arm-shaped member extending in the bottle insertion direction D1, and its rear end is rotatably supported by the bottom plate 66A. The interlocking piece 72 is biased upward by a spring member (not shown) and is in contact with the bottom surface of the bottle receiving portion 61 of the bottle mounting portion 60.

  The optical sensor 73 outputs a detection signal according to the moving position of the interlocking piece 72. The optical sensor 73 is, for example, a transmissive photo interrupter having a light emitting element (light emitting portion) and a light receiving element (light receiving portion). The light emitting element is a photodiode or the like that emits light toward the light receiving element. The light receiving element is, for example, a phototransistor that receives the light from the light emitting element and outputs the detection signal. The optical sensor 73 is arranged so that the interlocking piece 72 can enter the detection space between the light emitting element and the light receiving element. In the present embodiment, the interlocking piece 72 enters the detection space when the downward displacement amount of the bottle mounting portion 60 exceeds the reference value. At this time, the detection signal output from the optical sensor 73 is input to the control unit 8. The control unit 8 determines that the inside of the developer bottle 5 is filled with the waste developer 90 based on the input detection signal.

  As shown in FIG. 5, the piezoelectric sensor 80 is attached to the receiving portion 67 of the receiving portion 63. The piezoelectric sensor 80 has a flat pressure detection surface 84 for detecting pressure, and responds to the contact pressure when the contact pressure from the waste developer 90 is applied to the pressure detection surface 84. Output a detection signal. As the piezoelectric sensor 80, a piezo type sensor using a piezo element, a strain gauge type sensor using a strain gauge, or the like can be used.

  The piezoelectric sensor 80 is a sensor that detects the presence or absence of the waste developer 90 in the internal space 67A of the receiving portion 67. If the waste developer 90 overflows from the developer bottle 5 and flows back through the receiving unit 63 to reach the image forming unit 40 when the fullness detecting mechanism 70 fails, the image forming by the image forming unit 40 is only hindered. In addition, the waste developer 90 flowing back to the image forming unit 40 may cause a problem that the image forming unit 40 breaks down. The piezoelectric sensor 80 is provided in order to prevent such a problem from occurring. The detection signal output from the piezoelectric sensor 80 is input to the control unit 8. The control unit 8 determines whether the waste developer 90 is accumulated in the receiving unit 67 based on the input detection signal.

  As shown in FIG. 5, the receiving portion 67 has a mounting seat 81 formed integrally with the receiving portion 67, and a bracket 82 fixed to the mounting seat 81. The mounting seat 81 is formed on the outer peripheral wall of the receiving portion 67. The mounting seat 81 is formed with an insertion opening 86 communicating with the internal space 67A of the receiving portion 67. The insertion opening 86 penetrates the outer peripheral wall of the receiving portion 67 in a horizontal direction. The piezoelectric sensor 80 is attached to the receiving portion 67 such that the pressure detection surface 84 is exposed to the internal space 67A of the receiving portion 67 through the insertion opening 86. The piezoelectric sensor 80 has a cylindrical detection portion 80A having a pressure detection surface 84 at its tip and a flange 80B that abuts against the mounting seat 81, and the detection portion 80A is inserted into the insertion opening 86. Then, the flange 80B is brought into contact with the mounting seat 81. Then, in this state, the bracket 82 is fixed to the receiving portion 67 with a screw or the like so as to cover the piezoelectric sensor 80 from the outside.

  With the piezoelectric sensor 80 attached to the receiving portion 67, the pressure detection surface 84 is arranged at a position slightly separated from the inner surface 67B of the receiving portion 67 to the outside. The shape of the internal space 67A of the receiving portion 67 may be a cylindrical shape extending in the vertical direction or a rectangular tube shape. However, a portion of the inner surface 67B corresponding to the position where the piezoelectric sensor 80 is attached is formed in a planar shape parallel to the pressure detection surface 84.

  When the pressure detection surface 84 of the piezoelectric sensor 80 is exposed in the internal space 67A, the waste developer 90 falling downward in the internal space 67A may adhere to the pressure detection surface 84 and gradually increase in size. . In this case, due to the weight of the attached waste developer 90, an unexpected pressing force may be applied to the pressure detection surface 84. In this case, the piezoelectric sensor 80 may malfunction. Therefore, in the present embodiment, the cushioning sheet 91 (an example of the cushioning member) for preventing the malfunction of the piezoelectric sensor 80 is provided.

  As shown in FIG. 5, the buffer sheet 91 covers the pressure detection surface 84 and attenuates the pressure applied to the pressure detection surface 84. The buffer sheet 91 is provided inside the internal space 67A and is arranged so as to face the pressure detection surface 84. The cushioning sheet 91 of the present embodiment is a sheet member formed of a flexible member and having a sheet shape. As the cushioning sheet 91, a sheet member made of silicon rubber coated with a non-adhesive material having high non-adhesiveness (for example, fluororesin) is used.

  The cushioning sheet 91 is attached to the inner surface 67B with an adhesive or the like so as to close the insertion opening 86 from the inner space 67A side. As described above, since the pressure detection surface 84 is arranged at a position slightly separated from the inner surface 67B of the receiving portion 67 on the outer side, by providing the buffer sheet 91, the buffer sheet 91 and the pressure detection surface 84 are provided. A predetermined clearance is formed between them. This clearance is set to 1 mm, for example. The clearance is set within the range of 0 to 1 mm depending on the response of the piezoelectric sensor 80 and the like.

  Since such a buffer sheet 91 is provided, the developer bottle 5 becomes full, the carry-in relay section 64 also becomes full, and the waste developer 90 collects in the internal space 67A of the receiving section 67. When the entire surface of the buffer sheet 91 is covered, the waste developer 90 presses the buffer sheet 91 and bends the buffer sheet 91 to the pressure detection surface 84 side. At this time, the buffer sheet 91 contacts the pressure detection surface 84, and the contact pressure is appropriately detected by the piezoelectric sensor 80. On the other hand, when the developer bottle 5 is not full, the waste developer 90 falling downward in the internal space 67A of the receiving portion 67 contacts the surface of the buffer sheet 91. At this time, even if the contacted waste developer 90 adheres to the surface of the buffer sheet 91 and grows to a large extent, the weight of the falling direction due to the adhered matter only applies to the buffer sheet 91, and the pressure detection surface separated by the clearance is provided. 84 does not take. Therefore, it is possible to prevent an unexpected pressing force from being applied to the pressure detection surface 84 by the attached matter, and thus prevent the malfunction of the piezoelectric sensor 80. Further, since the buffer sheet 91 is coated with a non-adhesive material such as a fluororesin, it is possible to prevent the waste developer 90 falling in the internal space 67A from adhering to the buffer sheet 91, which causes a malfunction. It is possible to suppress the generation of deposits that become

[Second Embodiment]
The second embodiment of the present invention will be described below.

  In the above-described first embodiment, the internal space 67A of the receiving portion 67 is formed straight downward, and the example in which the piezoelectric sensor 80 is provided in the receiving portion 67 has been described. The configuration is not limited to this. For example, as shown in FIG. 7, the piezoelectric sensor 80 may be provided so that the pressure detection surface 84 is inclined downward with respect to the downward direction in which the waste developer 90 is guided in the internal space 67A. In the second embodiment of the present invention described below, the same components as those in the above-described first embodiment will be denoted by the same reference numerals, and the description thereof will be omitted.

  In the waste developer collecting section 6 of the present embodiment, as shown in FIG. 7, the receiving section 67 has a first tube section 671 and a second tube section 672. Further, the receiving portion 67 has an inclined mounting seat 81A (an example of an inclined portion) instead of the above-described mounting seat 81. As shown in FIG. 7, the first pipe portion 671 is a portion connected to the bellows pipe 68. In addition, the second pipe portion 672 is provided below the first pipe portion 671, and the inner diameter thereof is formed larger than the inner diameter of the first pipe portion 671. The mounting seat 81A is provided between the first pipe portion 671 and the second pipe portion 672. The mounting seat 81A is formed with an insertion opening 86 through which the detection portion 80A of the piezoelectric sensor 80 is inserted. At the insertion opening 86, the lower end 86A of the internal space 67A is located outside the upper end 86B. Therefore, when the detection portion 80A is inserted into the insertion opening 86 and the piezoelectric sensor 80 is attached to the attachment seat 81A, the pressure detection surface 84 inclines downward as shown in FIG. In this embodiment, the inclination angle θ of the pressure detection surface 84 is set to approximately 10 degrees. The inclination angle θ can be set to a predetermined value within the range of 0 <θ ≦ 45 °.

  The cushioning sheet 91 is attached to the inner surface 67B with an adhesive or the like so as to close the insertion opening 86 from the inner space 67A side. Therefore, the cushioning sheet 91 is also inclined at the same angle as the inclination angle θ. In this case as well, the above-described predetermined clearance is formed between the buffer sheet 91 and the pressure detection surface 84.

  Since the piezoelectric sensor 80 is attached in an inclined state and the buffer sheet 91 is also attached in an inclined state as described above, the waste developer 90 overflowing from the developer bottle 5 flows back into the internal space 67A, and When the bulk rises, it comes into contact with the inclined surface of the cushioning sheet 91. At this time, even if the waste developer 90 is not accumulated enough to cover the entire surface of the buffer sheet 91, if an upward force is applied from the waste developer 90 to the surface of the buffer sheet 91, the amount of the force is increased. The force presses the cushioning sheet 91 to bend the cushioning sheet 91 toward the pressure detection surface 84 side. At this time, the buffer sheet 91 contacts the pressure detection surface 84, and the contact pressure is appropriately detected by the piezoelectric sensor 80. As a result, the piezoelectric sensor 80 can be reacted early before the entire surface of the buffer sheet 91 is covered, and the responsiveness of the piezoelectric sensor 80 can be improved.

[Modification of cushioning member]
In each of the above-described embodiments, the cushioning sheet 91 is illustrated as an example of the cushioning member, but, for example, as shown in FIG. 8A, the cushioning sheet 91 is provided with the hemispherical projection 95. It is also possible to apply the buffer sheet 92. The projection 95 is formed integrally with the cushioning sheet 92, and is formed on the surface of the cushioning sheet 92 that faces the pressure detection surface 84. Specifically, the protrusion 95 is provided on a portion of the opposing surface of the cushioning sheet 92 that corresponds to the center of the pressure detection surface 84. It is generally known that the piezoelectric sensor 80 has good reactivity in the central portion of the pressure detection surface 84. Therefore, the responsiveness of the piezoelectric sensor 80 when the cushioning sheet 92 is bent becomes better.

  Further, it is also possible to apply the buffer cover 93 shown in FIG. 8B as the buffer member. The buffer cover 93 is a cover member directly attached to the outer peripheral edge of the pressure detection surface 84 with the above-described predetermined clearance provided between the buffer cover 93 and the pressure detection surface 84. The buffer cover 93 is formed of a flexible material like the buffer sheet 91 described above, and the surface of the sheet member made of silicon rubber is coated with a highly non-adhesive non-adhesive material (for example, fluororesin). It was done.

  Further, as the cushioning member, the elastic member 94 shown in FIG. 8C can be applied. The elastic member 94 is formed of a material such as a nonwoven fabric or a sponge member into a sheet shape, and is directly attached in a state of being in contact with the pressure detection surface 84. The surface of the elastic member 94 on the inner space 67A side is coated with a highly non-adhesive non-adhesive material (for example, fluororesin).

  Even with such a buffer cover 93 or elastic member 94, when the waste developer 90 is accumulated in the internal space 67A of the receiving portion 67, the presence or absence of the waste developer 90 in the internal space 67A can be reliably detected. It is possible.

[Third Embodiment]
The third embodiment of the present invention will be described below.

  In the above-described first embodiment, the configuration in which the cushioning sheet 91 as the cushioning member is attached so as to cover the pressure detection surface 84 of the piezoelectric sensor 80 is illustrated, but the present invention is not limited to this configuration. For example, as shown in FIG. 9, instead of the cushioning sheet 91, a magnet sheet 111 (an example of a first magnet member) may be attached so as to cover the pressure detection surface 84 of the piezoelectric sensor 80. In this case, a magnet plate 112 (an example of a second magnet member) is provided in a position facing the magnet sheet 111 in the internal space 67A of the receiving portion 67. In the third embodiment of the present invention described below, the same components as those in the first embodiment described above will be denoted by the same reference numerals, and the description thereof will be omitted.

  In the conventional configuration in which the pressure detection surface 84 is exposed in the internal space 67A, the waste developer 90 may adhere to the pressure detection surface 84 and cause the piezoelectric sensor 80 to malfunction. Therefore, in the present embodiment, the cleaning member 120 described later is provided in the internal space 67A to remove the waste developer 90 adhering to the pressure detection surface 84. However, when a relatively large amount of the waste developer 90 enters between the cleaning member 120 and the internal space 67A, the waste carrier 90b comes into contact with the pressure detection surface 84 so as to rub against the pressure detection surface 84. The waste toner 90a may be attached to the pressure detection surface 84. In order to solve such a problem, the waste developer collecting section 6 of this embodiment is provided with a magnet sheet 111 and a magnet plate 112.

  As shown in FIG. 9, in the waste developer collecting portion 6 of the present embodiment, a magnet sheet 111 (an example of a buffer member) for preventing malfunction of the piezoelectric sensor 80 and a magnet plate 112 are provided. . The strength (magnetic flux density) of each of the magnet sheet 111 and the magnet plate 112 is, for example, 30 [mT].

  The magnet sheet 111 is a so-called rubber magnet using nitrile rubber as a binder and has flexibility. The magnet sheet 111 is an anisotropic magnet made of ferrite, for example. The magnet sheet 111 is provided inside the internal space 67A and is arranged so as to face the pressure detection surface 84, similarly to the buffer sheet 91 described above. The magnet sheet 111 is attached to the inner surface 67B with an adhesive or the like so as to close the insertion opening 86 from the inner space 67A side. By providing the magnet sheet 111, a clearance of about 1 mm is formed between the magnet sheet 111 and the pressure detection surface 84. The clearance is set within the range of 0 to 1 mm depending on the response of the piezoelectric sensor 80 and the like. In the present embodiment, the magnet sheet 111 is provided such that the magnetic pole surface 115 (corresponding to the first magnetic pole surface) having a predetermined polarity (for example, N pole) faces the inner space 67A side of the receiving portion 67.

  The magnet plate 112 is provided in the internal space 67A with a predetermined gap ΔT (see FIG. 11) between the magnet plate 112 and the magnetic pole surface 115 of the magnet sheet 111. The magnet plate 112 is supported by a cleaning member 120, which will be described later, provided in the internal space 67A. The magnet plate 112 is formed in a thin rectangular plate shape. The magnet plate 112 is an anisotropic magnet made of ferrite, for example. The magnet plate 112 is formed thicker than the magnet sheet 111, and is not flexible. In the present embodiment, the magnet plate 112 is attached to the cleaning member 120 so that the magnetic pole surface 116 (corresponding to the second magnetic pole surface) having the same polarity (for example, N pole) as the magnetic pole surface 115 of the magnet sheet 111 faces the magnetic pole surface 115. It is supported. As a result, the magnet plate 112 is always kept parallel to the magnet sheet 111.

  A cleaning member 120 is provided in the internal space 67A. The cleaning member 120 is provided in the internal space 67A so as to be vertically movable. The cleaning member 120 is formed by winding a wire material such as a metal wire into a coil shape, and the upper end thereof is attached to the transport member 103. An eccentric shaft 108, which is separated from the center in the radial direction, is provided in the conveying member 103 at a position corresponding to the discharge port 106. At the upper end of the cleaning member 120, an engaging portion 124 in which a wire is bent in an arc shape is formed, and the engaging portion 124 engages with the eccentric shaft 108 with play. As a result, the cleaning member 120 is supported so as to be suspended by the eccentric shaft 108. Therefore, when the transport member 103 is rotationally driven, the cleaning member 120 reciprocates in the vertical direction as the transport member 103 rotates. More precisely, the cleaning member 120 is displaced vertically and horizontally as the transport member 103 rotates. The cleaning member 120 is displaced in the internal space 67A according to the rotation of the transport member 103, so that the waste developer 90 attached to the inner surface 67B of the receiving portion 67 and the magnetic pole surface 115 of the magnet sheet 111 is contacted by the cleaning member 120. It is peeled off and dropped down.

  The cleaning member 120 is divided into a first coil portion 121 and a second coil portion 122 (an example of a contact portion) having an outer diameter (coil diameter) larger than that of the first coil portion 121. In the cleaning member 120, the first coil portion 121 is provided above the second coil portion 122. Mainly, the waste developer 90 attached to the inner surface 67B of the receiving portion 67 is stripped off by the contact of the first coil portion 121, and the waste developer 90 attached to the magnetic pole surface 115 is stripped off by the contact of the second coil portion 122. Be dropped.

  As shown in FIG. 10, the second coil portion 122 is arranged at a position facing the pressure detection surface 84 of the piezoelectric sensor 80 with the engagement portion 124 engaged with the eccentric shaft 108. The second coil portion 122 is formed in a square coil shape in which a wire is wound in a square shape. The second coil portion 122 is formed such that the wire is parallel to the magnetic pole surface 115 of the magnet sheet 111. The magnet plate 112 is attached to the second coil portion 122 (see FIG. 9). In the present embodiment, in the second coil portion 122, the magnet plate 112 is attached to the inner surface of the wire on the side of the magnet sheet 111 with an adhesive or the like. In addition, in FIG. 10, the illustration of the magnet sheet 111 and the magnet plate 112 is omitted.

  As described above, in the magnet sheet 111 and the magnet plate 112, the magnetic pole surfaces 115 and 116 of the same polarity face each other. Therefore, a repulsive force in a direction in which the magnet sheet 111 and the magnet plate 112 are separated from each other is generated. Since the cleaning member 120 is supported so as to be suspended from the eccentric shaft 108, the entire cleaning member 120 is displaced vertically and horizontally when the transport member 103 rotates and when there is no repulsive force. However, since the repulsive force acts on the magnet plate 112, when the conveying member 103 rotates, the engaging portion 124 is displaced vertically and horizontally, but the second coil portion 122 has a constant gap between the magnetic pole surfaces 115 and 116. While keeping ΔT (see FIG. 11), it reciprocates vertically.

  Since the magnet sheet 111 and the magnet plate 112 are provided as described above, when the waste developer 90 is discharged from the outlet pipe 107 to the receiving portion 67, even if the waste carrier 90b having magnetism tries to enter the gap ΔT. The waste carrier 90b is repelled by the magnetic force of the magnet sheet 111 and the magnet plate 112 before entering the gap ΔT. Specifically, as described above, the waste carrier 90b is a granular material of a soft magnetic material, and when it approaches the magnet sheet 111 or the magnet plate 112 and receives a magnetic field from either the magnet sheet 111 or the magnet plate 112. The waste carrier 90b itself is magnetically polarized and becomes a magnet. When the waste carrier 90b in such a magnetized state tries to enter the gap ΔT, the repulsive magnetic fields generated by the magnetic pole surfaces 115 and 116 of the magnet sheet 111 and the magnet plate 112 are magnetically attracted to both the magnetic pole surfaces 115 and 116. Without being repulsed, it is repelled upward by the repulsive magnetic field. As a result, in FIG. 11, it passes through between the left side surface of the magnet plate 112 (the surface opposite to the magnetic pole surface 116) and the inner surface 67B of the receiving portion 67 and falls downward (see the broken line arrow in FIG. 11). Therefore, the waste carrier 90b is prevented from contacting the magnetic pole surface 115 so as to rub against it, so that the waste carrier 90b and the waste toner 90a are prevented from adhering to the magnetic pole surface 115. As a result, the malfunction of the piezoelectric sensor 80 caused by the weight of the waste developer adhering to the magnetic pole surface 115 can be prevented when the developer bottle 5 is not full.

5: developer bottle 6: waste developer collecting section 10: image forming apparatus 40: image forming section 50: opening 67: receiving section 67A: internal space 80: piezoelectric sensor 81: pressure detection surface 91: buffer sheet 100: waste development Agent transport mechanism 103: transport member 111: magnet sheet 112: magnet plate 120: cleaning member 121: first coil portion 122: second coil portion

Claims (6)

A developer container having an opening through which the waste developer discharged from the image forming unit can flow;
A tubular guide flow path portion which is provided on the upper side of the opening portion and guides the waste developer from the image forming portion toward the opening portion,
The pressure detection surface is provided in the guide flow passage portion such that the pressure detection surface is exposed to the inside of the guide flow passage portion through the insertion opening formed in the outer peripheral wall of the guide flow passage portion, and the pressure applied to the pressure detection surface is adjusted. A developer detection sensor for detecting the presence or absence of the waste developer in the guide flow path portion based on the:
The first magnetic pole surface, which is provided inside the guide flow path portion so as to face the pressure detection surface and covers the pressure detection surface and has a predetermined polarity, is directed toward the inner side of the guide flow path portion. A first magnet member,
A cleaning member provided inside the guide flow path portion so as to be movable up and down, and contacting and removing the developer adhering to the first magnetic pole surface;
It is attached to the cleaning member with a predetermined gap from the first magnet member, and is arranged so that a second magnetic pole surface having the same polarity as the first magnetic pole surface faces the first magnetic pole surface. And a second magnet member, and a waste developer recovery device. Further comprising a spiral carrying member for carrying the waste developer from the image forming section to the guide flow path section by being driven to rotate,
The cleaning member has a contact portion, one end of which is attached to an eccentric shaft provided on the transport member, and the other end of which is in contact with and removes the developer attached to the first magnetic pole surface.
The waste developer recovery device according to claim 1, wherein the second magnet member is supported by the contact portion.   The said contact part is formed in the shape of the square coil which the wire was wound in square shape, and the said 2nd magnet member is attached to the said 1st magnet member side in the said contact part. The waste developer recovery device described.   The waste developer recovery device according to claim 1, wherein the first magnet member is a flexible sheet-shaped member that closes the insertion port from the inside of the guide flow path portion.   The waste developer recovery device according to claim 4, wherein a predetermined clearance is provided between the pressure detection surface and the first magnet member. An image forming unit that transfers a toner image to an image carrier using a developer containing toner,
An image forming apparatus comprising: the waste developer collecting device according to claim 1.

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