JP5758032B2 - Developing device and image forming apparatus including the same - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine, a facsimile, or a printer having a detachable developing device, and more particularly to a connection structure between a developing device and a developer supply mechanism that supplies developer to the developing device. .

  2. Description of the Related Art Conventionally, a developing device mounted on an image forming apparatus is filled with a certain amount of developer (toner) in the developing device for easy maintenance, and is replaced when the developer is exhausted. However, the developing device cannot be replaced frequently from an economic point of view, and the capacity of the developer must be increased in order to form a certain number of images. . Therefore, in order to reduce the size of the developing device, a developing device that supplies a developer from a developer supply mechanism such as a toner container and an intermediate hopper provided separately from the developing device has been proposed.

  Further, when the developer supply mechanism and the developing device cannot be disposed adjacent to each other due to layout restrictions inside the image forming apparatus, as shown in Patent Documents 1 and 2, the developer supply mechanism and the developing device are communicated. A configuration in which a flexible developer supply path such as a toner feed pipe or a transport pipe is provided is used.

JP 2003-270950 A JP 2005-316287 A

  By the way, in the image forming apparatus as described above, in order to simplify the replacement work and maintenance work of the developing device, it is possible to remove only the developing device while leaving the developer supply mechanism on the image forming apparatus main body side. It is preferable to do.

  However, in configurations such as Patent Documents 1 and 2, since the flexible developer supply path is flexibly connected to the developer supply mechanism and the developing device, the developer supply path and the developer supply mechanism or the developing device There was a problem that the connection strength of the was weakened. Further, in the configuration of Patent Document 1, since the plug provided at the tip of the toner feeding tube is connected to the swing shaft of the developing unit, it is necessary to connect or disconnect the plug each time the developing unit is attached or detached. The attaching / detaching operation becomes complicated.

  Further, when the developing device is attached to or detached from the image forming apparatus main body, the developing roller is a predetermined distance from the photosensitive drum in order to avoid interference between the developing roller (developer carrier) and the photosensitive drum (image carrier). It is necessary to attach and detach the developing device in a state in which the developing device is moved to a position that is separated from the developing device. However, in the operating position, if the positional relationship between the developing roller and the photosensitive drum varies, an image defect occurs. When the developing device is moved, if the connecting portion of the developer supply mechanism connected to the developer supply port of the developing device is fixed to the image forming apparatus main body side, the connecting portion and the developing device are moved when the developing device is moved. The positional relationship between the developer supply port and the developer supply mechanism may shift, resulting in poor connection between the developing device and the developer supply mechanism, or the positional relationship between the developing roller and the photosensitive drum may vary due to uneven rotation. It was.

  Even if connection failure does not occur, if the opening of the developer supply mechanism remains open when the developing device is attached or detached, the developer adhering to the opening falls into the image forming apparatus main body and the inside of the apparatus Could be contaminated.

  In view of the above problems, the present invention can easily remove only the developing device while leaving the developer supplying mechanism on the apparatus main body side, and connects the developer supplying mechanism and the developing device when the developing device is attached or detached. It is an object of the present invention to provide an image forming apparatus in which defects and leakage of developer and image defects due to fluctuations in the positional relationship between the developing roller and the photosensitive drum do not occur.

  In order to achieve the above object, the present invention provides a developer that is disposed to face an image carrier on which an electrostatic latent image is formed, and that supplies the developer to the image carrier in a region facing the image carrier. A developing device having a carrier, and the developing device can be selectively disposed at a detachable position where the developer carrier is separated from the image carrier and a development position where the developer can be supplied to the image carrier. In the image forming apparatus including a support frame and a developer supply mechanism that supplies a developer to the developing device, a connecting portion of the developer supply mechanism with the developing device includes the attachment / detachment position and the development position. A shutter member that opens and closes a replenishing port formed in the developer supply mechanism using a moving operation of the developing device as a driving force is mounted, and the shutter member is mounted from the attachment / detachment position of the developing device. Transfer to the development position The replenishing port is opened by the operation, the replenishing port is closed by the movement operation of the developing device from the developing position to the attaching / detaching position, and the moving direction of the developing device is different from the opening / closing direction of the shutter member. It is a feature.

  According to the present invention, in the image forming apparatus having the above-described configuration, the developer supply mechanism is disposed at a position that does not overlap with the attaching / detaching direction of the developing device.

  According to the first configuration of the present invention, since the developing device is movably connected to the developer supply mechanism fixed in the image forming apparatus main body, the configuration of the connecting portion is simplified and the rigidity is increased. Can do. In addition, when the developing device is moved from the developing position to the attaching / detaching position, the shutter member automatically closes the replenishing port of the developer supply mechanism, so that the developer leakage from the replenishing port is ensured when the developing device is attached / detached. Can be prevented. Also, when the developing device is moved from the attach / detach position to the developing position, the shutter member automatically opens the replenishment port of the developer supply path, so there is a risk that the shutter member may be forgotten to be opened when the developer is replenished with the developer. Disappear. Furthermore, since the operating direction of the shutter member and the moving direction of the developing device are different, the shutter member can be operated without affecting the positional relationship between the developer carrier and the image carrier.

  According to the second configuration of the present invention, in the image forming apparatus having the first configuration, the developer supply mechanism is disposed at a position that does not overlap with the attaching / detaching direction of the developing device, thereby providing the developer supply mechanism. The developing device can be attached and detached without removing the image forming apparatus, and the maintainability of the image forming apparatus is improved.

1 is a schematic cross-sectional view of an image forming apparatus 100 according to an embodiment of the present invention. Side sectional view of the developing device 4 mounted in the image forming apparatus 100 of the present invention. 1 is an external perspective view showing the positional relationship among the developing device 4, the toner container 5, and the intermediate hopper 6 in the image forming apparatus 100 of FIG. FIG. 1 is an external perspective view showing the positional relationship among the developing device 4, the toner container 5, and the intermediate hopper 6 in the image forming apparatus 100 as viewed from the back side of FIG. FIG. 4 is an external perspective view showing a state in which the toner container 5 is removed from the state of FIG. The perspective view which shows the state which the support frame 41 and the frame fixing member 50 arrange | positioned at the image forming apparatus 100 main body side connected. A perspective view of the support frame 41 and the development release lever 44 as viewed from below. FIG. 7 is a partially enlarged view around one nail portion 46. A perspective view of the frame fixing member 50 as viewed from above Exploded perspective view of toner container 5 The perspective view which looked at the connection part of the image development apparatus 4 and the toner conveyance path 70 from upper direction. The perspective view of the guide part 26 provided in the developing device 4 A perspective view of a shutter member 80 mounted on the toner conveyance path 70 The perspective view which looked at the connection part of developing device 4 and toner conveyance way 70 when moving developing device 4 to an attachment or detaching position from the upper part. The perspective view which shows the positional relationship of the guide part 26 and the shutter member 80 when moving the image development apparatus 4 to an attachment or detachment position. The perspective view which looked at the connection part of developing device 4 and toner conveyance way 70 when moving developing device 4 to a development position from the upper part. The perspective view which shows the positional relationship of the guide part 26 and the shutter member 80 when the developing device 4 is moved to a developing position.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of an image forming apparatus 100 according to an embodiment of the present invention. In the main body of the image forming apparatus (for example, a monochrome multifunction peripheral) 100, an image forming portion P for forming a monochrome image by each process of charging, exposure, development, and transfer is disposed.

  In the image forming unit P, along the rotation direction of the photosensitive drum 1 (counterclockwise direction in FIG. 1), the charging unit 2, the exposure unit 3, the developing device 4, the transfer roller 7, the cleaning device 8, and the static eliminating device. (Not shown) is provided. In the image forming unit P, the image forming process for the photosensitive drum 1 is executed while rotating the photosensitive drum 1 in the counterclockwise direction in FIG.

  The photosensitive drum 1 is formed, for example, by laminating a photosensitive layer on an aluminum drum, and the charging unit 2 charges the surface. Then, an electrostatic latent image in which charging is attenuated is formed on the surface that has received a laser beam from the exposure unit 3 described later. The above-mentioned photosensitive layer is not particularly limited. For example, amorphous silicon (a-Si) having excellent durability, or an organic photosensitive layer (high-resolution image can be obtained with little generation of ozone during charging). OPC) and the like are preferable.

  The charging unit 2 uniformly charges the surface of the photosensitive drum 1. For example, a corona discharge device that discharges by applying a high voltage using a thin wire or the like as an electrode is used as the charging unit 2. Instead of the corona discharge device, a contact-type charging device that applies a voltage in a state where a charging member typified by a charging roller is in contact with the surface of the photoreceptor may be used. The exposure unit 3 irradiates the photosensitive drum 1 with a light beam (for example, a laser beam) based on the document image data read by the image reading unit 18 to form an electrostatic latent image on the surface of the photosensitive drum 1.

  The developing device 4 forms toner images by attaching toner to the electrostatic latent image on the photosensitive drum 1. The toner is supplied to the developing device 4 from the toner container 5 via the intermediate hopper 6. Here, a single-component developer (hereinafter also simply referred to as toner) composed only of magnetic toner components is accommodated in the developing device 4. Details of the developing device 4, the toner container 5, and the intermediate hopper 6 will be described later.

  The transfer roller 7 transfers the toner image formed on the surface of the photosensitive drum 1 to the sheet conveyed through the sheet conveyance path 11 without disturbing the toner image. The cleaning device 8 includes a cleaning roller, a cleaning blade, and the like that are in linear contact with the longitudinal direction of the photosensitive drum 1, and removes residual toner remaining on the surface of the photosensitive drum 1 after the toner image is transferred to the paper. To do.

  The image reading unit 18 includes a scanner lamp that illuminates the document during copying, a scanning optical system equipped with a mirror that changes the optical path of reflected light from the document, and a condensing lens that focuses the reflected light from the document to form an image. And a CCD sensor or the like (both not shown) that converts the imaged image light into an electrical signal, and reads a document image and converts it into image data.

  When performing a copy operation, the image reading unit 18 reads the image data of the document and converts it into an image signal. On the other hand, in the image forming unit P, the photosensitive drum 1 that rotates counterclockwise in the drawing is uniformly charged by the charging unit 2, and the exposure unit 3 is based on the document image data read by the image reading unit 18. Emits a laser beam (light beam) onto the photosensitive drum 1 to form an electrostatic latent image based on the image data on the surface of the photosensitive drum 1. Thereafter, the developing device 4 attaches toner to the electrostatic latent image to form a toner image.

  A sheet is conveyed from the sheet storage unit 10 through the sheet conveyance path 11 and the registration roller pair 13 at a predetermined timing toward the image forming unit P on which the toner image is formed as described above. The toner image on the surface of the photosensitive drum 1 is transferred onto the sheet by the transfer roller 7. The sheet on which the toner image has been transferred is separated from the photosensitive drum 1, conveyed to the fixing unit 9, and heated and pressed to fix the toner image on the sheet.

  The paper that has passed through the fixing unit 9 is sorted in the transport direction by the transport guide member 16 disposed in the branching section of the paper transport path 11, and is sent as it is (or after being sent to the reverse transport path 17 and copied on both sides). The paper is discharged to the paper discharge unit 15 via the discharge roller pair 14.

  FIG. 2 is a side sectional view of the developing device 4. As shown in FIG. 2, a first storage chamber 21 and a second storage chamber 22 are formed in the developing container 20 by a partition wall (not shown) formed integrally with the developing container 20. A first stirring screw 23 is disposed in the first storage chamber 21, and a second stirring screw 24 is disposed in the second storage chamber 22. A toner supply port 20a is provided in an upper portion of the developing container 20, and is stored in the toner container 5 (see FIG. 1) according to a detection result of a toner sensor (not shown) that detects the amount of toner in the developing container 20. The toner thus supplied is supplied through the intermediate hopper 6 (see FIG. 1). In addition, a guide portion 26 to which a toner conveyance path 70 (see FIG. 4), which will be described later, is connected is provided so as to surround the toner supply port 20a.

  Each of the first stirring screw 23 and the second stirring screw 24 has a structure in which a spiral blade is provided around the support shaft, and is rotatably supported by the developing container 20 in a state of being parallel to each other. Yes. Note that there are no partition walls at both ends of the longitudinal direction of the developing container 20 (the direction perpendicular to the paper surface of FIG. 2), which is the axial direction of the first stirring screw 23 and the second stirring screw 24, and the first stirring screw. 23, the toner can be transferred between the second stirring screws 24. Thus, the first stirring screw 23 conveys the toner in the first storage chamber 21 to the second storage chamber 22 while stirring, and the second stirring screw 24 transfers the toner transferred to the second storage chamber 22. It is conveyed while stirring and supplied to the developing roller 25.

  The developing roller 25 is rotatably supported by the developing container 20 in a state parallel to the first stirring screw 23 and the second stirring screw 24. A magnet body 27 made of a permanent magnet having a plurality of magnetic poles is fixed inside the developing roller 25. A toner thin layer is formed by attaching (carrying) toner onto the surface of the developing roller 25 by the magnetic force of the magnet body 27. A part of the outer peripheral surface of the developing roller 25 is exposed from the developing container 20, and the exposed part is disposed so as to face the photosensitive drum 1 (see FIG. 1).

  Then, the developing roller 25 on which the toner thin layer is formed rotates according to the rotation of the photosensitive drum 1 to supply toner to the photosensitive layer of the photosensitive drum 1. The first stirring screw 23, the second stirring screw 24, and the developing roller 25 are rotationally driven at a predetermined speed by a motor (not shown) and a gear train. In addition, magnetic seal members 28 for preventing leakage of the developer from the gap between the developing container 20 and the developing roller 25 are disposed at both ends of the developing roller 25.

  The regulating blade 29 is formed such that its longitudinal direction is larger than the maximum developing width of the developing roller 25, and is arranged at a predetermined interval from the developing roller 25, so that the amount of toner supplied to the photosensitive drum 1 can be reduced. A layer thickness regulating portion 30 to be regulated is formed. The gap of the layer thickness regulating portion 30 is set to about 0.2 mm to 0.4 mm. As the material of the regulating blade 29, magnetic or non-magnetic SUS (stainless steel) or the like is used. Here, a permanent magnet 31 is attached to a magnetic regulating blade 29 to provide magnetism.

  The magnet body 27 has a plurality of magnetic poles (not shown) composed of N poles and S poles. Since the magnetic poles of the magnet body 27 are parallel to the regulating blade 29, the poles are concentrated on the tip of the regulating blade 29, and a magnetic field in a direction attracting the layer thickness regulating portion 30 is generated.

  By this magnetic field, a toner chain (magnetic brush) in which toner is continuous is formed between the regulating blade 29 and the developing roller 25. Then, the layer is regulated by passing through the layer thickness regulating unit 30, and a thin toner layer is formed on the developing roller 25. By arranging the permanent magnet 31 on the regulating blade 29, the regulating force is increased by the magnetic field generated in the layer thickness regulating section 30 as well as the interval between the layer thickness regulating sections 30, and a thin toner layer of several tens of μm is formed on the developing roller 25. Form. On the other hand, the toner that has not been used for forming the toner thin layer stays along the upstream side surface (lower side in FIG. 2) of the regulating blade 29. Thereafter, when the developing roller 25 rotates in the clockwise direction in FIG. 2 and the toner chain moves to a position facing the photosensitive drum 1, the toner chain forms a toner image with a certain distance from the surface of the photosensitive drum 1. Form.

  3 and 4 are external perspective views showing the positional relationship among the developing device 4, the toner container 5, and the intermediate hopper 6 in the image forming apparatus 100 of FIG. 1, and FIG. 5 is a diagram in which the toner container 5 is removed from the state of FIG. It is an external appearance perspective view which shows a state. 3 shows a state in which the developing device 4, the toner container 5, and the intermediate hopper 6 are viewed from the back side of the image forming apparatus 100 (the back side in FIG. 1).

  The developing device 4 is placed on a support frame 41 that is movable in the horizontal direction (arrow AA ′ direction) with respect to the main body of the image forming apparatus 100 (see FIG. 1). When the support frame 41 moves in the direction of arrow A, the developing device 4 is positioned so that the developing roller 25 faces the photosensitive drum 1 with a predetermined gap and toner can be supplied to the photosensitive drum 1 ( Hereinafter, it is arranged at a developing position). On the other hand, when the support frame 41 moves in the direction of the arrow A ′, the developing device 4 has a position where the developing roller 25 is separated from the photosensitive drum 1 and is detachable from the main body of the image forming apparatus 100 (hereinafter, referred to as an detaching position). Placed in.

  The developing device 4 arranged at the attaching / detaching position is attached to and detached from (attached to) the support frame 41 by being inserted or pulled out along the bottom surface of the support frame 41 in the direction perpendicular to the paper surface of FIG. Further, when the developing device 4 is disposed at the developing position, toner can be supplied from the developing device 4 to the photosensitive drum 1. A moving mechanism of the support frame 41 will be described later.

  The intermediate hopper 6 includes a hopper upper part 6a fixed to the main body of the image forming apparatus 100 and to which the toner container 5 is mounted, and a hopper lower part 6b connected to the hopper upper part 6a. In the hopper upper part 6a, a rotating shaft 61 on which the toner container 5 is rotatably supported and a paddle 63 that rotates around the rotating shaft 61 together with the toner container 5 are disposed. The hopper lower part 6b is connected to the toner supply port 20a of the developing device 4 so that a toner conveying path 70 for conveying the toner protrudes downward, and the inside of the hopper lower part 6b communicates with the inside of the toner conveying path 70. doing. The toner conveyance path 70 is formed of a material having rigidity, and a spiral (not shown) for transferring the toner in the intermediate hopper 6 to the developing device 4 is disposed in the toner conveyance path 70.

  The toner container 5 has four engaging projections 55b protruding from one end of the outer peripheral surface of a cylindrical container body 55, and engages with the engagement projection 55b on the image forming apparatus 100 body side. A ring-shaped coupling 33 and a motor 35 that rotationally drives the coupling 33 are arranged.

  An end portion 70a (see FIG. 11) on the developing device 4 side of the toner conveyance path 70 is slidably inserted into the guide portion 26 of the developing device 4. With this configuration, the guide unit 26 functions as a link member that connects the developing device 4 to the toner conveyance path 70 so as to be horizontally movable. It can be reciprocated (translated) in the direction.

  Next, the moving mechanism of the support frame 41 will be described. 6 is a perspective view showing a state in which the support frame 41 and the frame fixing member 50 arranged on the main body side of the image forming apparatus 100 are connected. FIG. 7 shows the support frame 41 and the development release lever 44 from below. FIG. 8 is a partially enlarged view of the vicinity of one claw portion 46 in FIG. 7 (inside the broken line circle S in FIG. 7), and FIG. 9 is a perspective view of the frame fixing member 50 as viewed from above. In FIG. 6, the development release lever 44 is not shown.

  The development release lever 44 is fixed to one end of a shaft 45 that is rotatably supported below the support frame 41. Two claws 46 are provided in the vicinity of both ends of the shaft 45, and the shaft 45 and the claws 46 are rotated by operating the development release lever 44. On the back side of the support frame 41, a pair of rail portions 41 a, a pair of spring receiving portions 48 that receive one end of the coil spring 47, and a pair of protrusions 49 that are disposed to face the claw portions 46 are formed. Yes.

  The frame fixing member 50 is fixed to the main body side of the image forming apparatus 100, and a rail engagement groove 51 that engages with the rail portion 41 a of the support frame 41 and a spring space 53 that accommodates the coil spring 47 are formed. . That is, both ends of the coil spring 47 are in contact with the spring receiving portion 48 and the inner wall surface at the left end of the spring space 53, and normally, the spring receiving portion 48 of the support frame 41 approaches the frame fixing member 50 (arrow A). Direction) is acting.

  When the development release lever 44 is rotated in the arrow C direction from the state of FIG. 8, the shaft 45 and the claw portion 46 are also rotated in the same direction, and the tip of the claw portion 46 presses the side surface of the protrusion 49. As a result, the support frame 41 moves in the direction of the arrow A ′, and the developing device 4 (see FIG. 4) is disposed at the attachment / detachment position. Further, since the spring receiving portion 48 moves in the direction of the arrow A ′ together with the support frame 41, the coil spring 47 is pressed against the inner wall surface at the left end of the spring space 53 and compressed.

  Next, when the development release lever 44 is rotated in the direction of the arrow C ′ to return to the state shown in FIG. 8, the shaft 45 and the claw portion 46 are also rotated in the same direction. Separate. As a result, the compressed coil spring 47 expands and presses the spring receiving portion 48, so that the support frame 41 moves in the direction of arrow A, and the developing device 4 (see FIG. 4) is disposed at the developing position.

  FIG. 10 is an exploded perspective view of the toner container 5. The toner container 5 includes a cylindrical container body 55 and caps 56 a and 56 b that are attached to both ends of the container body 55. A spiral rib 55 a is formed on the inner wall surface of the container main body 55, and the toner container 5 is rotated on the outer peripheral surface of the end portion (left end in FIG. 10) of the container main body 55 located on the front side of the image forming apparatus 100. An engaging convex portion 55b that engages with a coupling 33 (see FIG. 3) for driving is provided in a protruding manner.

  Two fan-shaped toner discharge ports 57 are formed in the cap 56a on the intermediate hopper 6 side. A container shutter 58 having an opening 58a having substantially the same shape as the toner discharge port 57 is disposed outside the cap 56a. The cap 56b on the coupling 33 side is detachable from the container main body 55, and the cap 56b is removed to fill the container main body 55 with toner.

  When the toner container 5 supported on the rotation shaft 61 (see FIG. 5) of the intermediate hopper 6 is rotated forward (rotated in the clockwise direction in FIG. 10), the toner container 5 is accommodated in the container main body 55 by the progress of the phase of the rib 55a. The toner also gradually moves from the cap 56b side to the cap 56a side (intermediate hopper 6 side) along the axial direction (arrow F direction). Further, the opening 58a of the container shutter 58 is disposed at a position where it overlaps with the toner discharge port 57 of the cap 56a when the container main body 55 rotates forward.

  Therefore, by rotating the container main body 55 forward, the toner in the container main body 55 is supplied to the intermediate hopper 6 through the toner discharge port 57 and the opening 58a. On the other hand, when the container body 55 is rotated in the reverse direction, the opening 58a of the container shutter 58 moves to a position where it does not overlap the toner discharge port 57 of the cap 56a, and the toner discharge port 57 is closed.

  FIG. 11 is a perspective view of a connecting portion between the developing device 4 and the toner conveyance path 70 as viewed from above. As shown in FIG. 11, a shutter member 80 is rotatably attached to an end portion 70 a on the developing device 4 side of the toner conveyance path 70. Further, a supply port 71 (see FIG. 15) is opened at the lower portion of the end portion 70a. The developing device 4 and the toner conveyance path 70 are connected by inserting the end portion 70 a on which the shutter member 80 is mounted into the guide portion 26. The shutter member 80 opens and closes the replenishing port 71 by moving relatively horizontally in the guide portion 26 while rotating as the developing device 4 moves horizontally in the AA ′ direction.

  FIG. 12 is a perspective view of the guide portion 26 provided in the developing device 4, and FIG. 13 is a perspective view of the shutter member 80 attached to the toner conveyance path 70. As shown in FIG. 12, the guide part 26 is formed in a cylindrical shape having a substantially elliptical cross section, and one end (the front side in FIG. 12) into which the shutter member 80 is inserted is open. A toner supply port 20a is formed on the lower surface of the guide portion 26, and a guide groove 60 bent in an L shape including a vertical groove portion 60a and a horizontal groove portion 60b is formed on the inner wall surface on the back side of the guide portion 26. ing. Further, a stepped portion 62 is formed so that a substantially half (left half in FIG. 12) of the lower portion of the opening edge 26a is cut away to the back side.

  As shown in FIG. 13, the shutter member 80 is formed in a cylindrical shape, and one end (left end in FIG. 13) into which the end of the toner conveyance path 70 is inserted is opened. A rectangular opening 81 is formed on the outer peripheral surface of the shutter member 80, and a protrusion 83 extending in the radial direction from the central axis of the cylinder projects from the tip of the shutter member 80. A flange 85 is formed at the opening edge of the shutter member 80 so as to protrude in the same direction as the direction in which the protrusion 83 extends.

  Further, the shutter member 80 is formed with a claw portion 87 that engages with the end portion 70 a of the toner conveyance path 70. The claw portion 87 rotatably engages the shutter member 80 with the end portion 70a and prevents the shutter member 80 from coming off from the end portion 70a. Before the developing device 4 is inserted, the shutter member 80 is held in a posture in which the projection 83 is vertical by a spring member (not shown) as shown in FIG.

  Next, the opening / closing mechanism of the supply port 71 by the shutter member 80 will be described in detail. 14 is a perspective view of a connecting portion between the developing device 4 and the toner conveyance path 70 when the developing device 4 is moved to the attachment / detachment position, and FIG. 15 is a perspective view of the developing device 4 moved to the attachment / detachment position. It is a perspective view which shows the positional relationship of the guide part 26 and the shutter member 80 when it is made to do. When the developing device 4 is attached to the image forming apparatus 100 by moving the support frame 41 (see FIG. 4) in the direction of arrow A ′, the end portion 70a of the toner conveyance path 70 is a guide portion as shown in FIGS. 26 is inserted to the left as viewed from the opening side.

  At this time, the projection 83 of the shutter member 80 is fitted in the longitudinal groove 60a (see FIG. 12) of the guide groove 60, and the opening 81 is located at a position spaced apart from the supply port 71 of the end 70a by about 90 °. . That is, the supply port 71 is closed by the shutter member 80.

  FIG. 16 is a perspective view of a connecting portion between the developing device 4 and the toner conveyance path 70 when the developing device 4 is moved to the developing position, and FIG. 17 is a perspective view when the developing device 4 is moved to the developing position. It is a perspective view which shows the positional relationship of the guide part 26 and the shutter member 80 when it is made to do. In the state shown in FIG. 14, when the support frame 41 (see FIG. 4) is moved in the direction of arrow A and the developing device 4 is placed in the developing position, the guide portion 26 of the developing device 4 is also moved in the direction of arrow A. As the developing device 4 moves, the end portion 70a of the toner conveyance path 70 relatively moves to the right when viewed from the opening side of the guide portion 26, as shown in FIGS.

  The shutter member 80 attached to the end portion 70a is positioned so that the projection 83 fitted in the longitudinal groove portion 60a of the guide groove 60 moves to the lateral groove portion 60b on the back side in the insertion direction, and the projection 83 becomes horizontal. change. On the other hand, the flange portion 85 rides on the step portion 62 on the front side in the insertion direction. As a result, the shutter member 80 rotates in the clockwise direction of FIG. 17, and the opening 81 is disposed at a position overlapping the supply port 71 to open the supply port 71. Further, the end portion 70a relatively moves from the left side to the right side in the guide portion 26, so that the supply port 71 is disposed at a position facing the toner supply port 20a. As a result, the toner conveyance path 70 and the developing device 4 are communicated with each other, and toner can be supplied from the toner conveyance path 70 to the developing device 4.

  On the other hand, when removing the developing device 4 from the image forming apparatus 100, the end portion 70a of the toner conveyance path 70 is viewed from the opening side of the guide portion 26 by moving the developing device 4 to the attaching / detaching position shown in FIG. The replenishing port 71 is closed by the shutter member 80 by moving relatively to the left side and rotating the shutter member 80 in the reverse direction (counterclockwise direction in FIG. 17).

  A slit 90 for elastically deforming the claw portion is present around the claw portion 87 of the shutter member 80, but the position where the shutter member 80 closes the supply port 71 (see FIG. 15) and the supply port 71 are opened. The claw portion 87 and the slit 90 are always positioned above the shutter member 80 even when rotated with respect to the position (see FIG. 17). Therefore, there is no possibility that the toner in the toner conveyance path 70 leaks from the slit 90.

  According to the above configuration, the developing device 4 can be selectively arranged at the developing position and the attaching / detaching position with the toner container 5 and the intermediate hopper 6 left in the main body of the image forming apparatus 100. Further, since the toner container 5 and the intermediate hopper 6 are not arranged at a position overlapping the attaching / detaching direction of the developing device 4 (front side in FIG. 4), the developing device 4 can be attached / detached without removing the toner container 5 and the intermediate hopper 6. can do. Accordingly, the developing device 4 and the toner container 5 can be separately attached to and detached from the image forming apparatus 100, and the maintainability of the image forming apparatus 100 is improved.

  Further, when the developing device 4 is moved to the developing position or the attaching / detaching position, the end portion 70a of the toner conveyance path 70 moves relatively horizontally in the guide portion 26, so that the end portion 70a (the shutter member 80) and the guide portion are moved. 26 is maintained. Accordingly, it is possible to effectively prevent the occurrence of poor connection between the toner conveyance path 70 and the developing device 4 due to the movement of the developing device 4. Further, since the intermediate hopper 6 and the developing device 4 are connected using the toner transfer path 70 having rigidity, the connection strength between the toner transfer path 70 and the intermediate hopper 6 or the developing device 4 can be increased.

  In addition, since the shutter member 80 closes the supply port 71 of the toner transport path 70 in conjunction with the movement of the developing device 4 to the attachment / detachment position, toner leakage from the supply port 71 during the attachment / detachment of the development device 4 is ensured. Can be prevented. Further, since the shutter member 80 opens the replenishment port 71 of the toner conveyance path 70 in conjunction with the movement of the developing device 4 to the development position, there is no possibility of forgetting to open the shutter member 80 at the time of toner replenishment.

  Further, since the operating direction (rotational direction) of the shutter member 80 and the moving direction (arrow AA ′ direction) of the developing device 4 are different, the load due to the opening / closing operation of the shutter member 80 is the positional relationship between the developing roller 25 and the photosensitive drum 1. It does not affect the pressing to keep the constant. Therefore, the shutter member 80 can be operated without affecting the positional relationship between the developing roller 25 and the photosensitive drum 1, and the occurrence of image defects can be suppressed.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of this invention. For example, in the above embodiment, the configuration using the developing device 4 using the magnetic one-component developer as shown in FIG. 2 has been described. However, the present invention is not limited to this, and the two-component developer composed of toner and carrier is used. A developing device using For example, the present invention can be applied to a developing device that uses a magnetic roller and a developing roller and moves a toner only on the developing roller while leaving a carrier on the magnetic roller to form a thin toner layer. Further, the toner container 5 is not limited to the method of moving the toner inside by rotating the container main body 55 as shown in FIG. 10, but a method of arranging a paddle or a spiral for conveying the toner in the container main body is adopted. You can also

  The present invention is applicable to an image forming apparatus having a detachable developing device. By utilizing the present invention, the strength of connection between the developer supply mechanism and the developing device is increased, the occurrence of poor connection between the developer supply mechanism and the developing device due to the movement of the developing device to the development position or the attachment / detachment position, and the development device It is possible to effectively prevent the developer leakage from the connecting portion of the developer supply mechanism at the time of attachment / detachment, and it is possible to provide an image forming apparatus excellent in maintainability.

1 Photosensitive drum (image carrier)
4 Developing device 5 Toner container 6 Intermediate hopper (developer supply mechanism)
6a Upper hopper 6b Lower hopper 20 Developing container 20a Toner supply port 25 Developing roller (developer carrier)
26 Guide part 41 Support frame 44 Development release lever 50 Frame fixing member 60 Guide groove 62 Step part 70 Toner conveyance path (developer supply mechanism)
70a end (connection part)
71 Supply Port 80 Shutter Member 81 Opening 83 Protrusion 85 Flange 100 Image Forming Apparatus

Claims (2)

A developing device having a developer carrier disposed opposite to an image carrier on which an electrostatic latent image is formed, and supplying a developer to the image carrier in a region facing the image carrier;
A support frame which can be selectively disposed in the developing device at a detachable position where the developer carrier is separated from the image carrier and a development position where the developer can be supplied to the image carrier;
A developer supply mechanism for supplying a developer to the developing device;
In an image forming apparatus comprising:
The connecting portion of the developer supply mechanism with the developing device has a replenishing port formed in the developer supplying mechanism with a driving force of the movement of the developing device between the attach / detach position and the developing position. A shutter member that opens and closes is mounted. The shutter member opens the replenishment port by a movement operation of the developing device from the attach / detach position to the developing position, and the developing device moves from the developing position to the attach / detach position. The image forming apparatus is characterized in that the replenishing port is closed by the moving operation, and the moving direction of the developing device is different from the opening / closing direction of the shutter member.   The image forming apparatus according to claim 1, wherein the developer supply mechanism is disposed at a position that does not overlap with a direction in which the developing device is attached or detached.

Images