JP2009058617A - Developer replenisheing device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent load acted on a developer feed member from becoming unstable due to slide contact of the developer feed member and a seal member, and to prevent fluttering sound from occurring. <P>SOLUTION: A toner replenishing device 7 for replenishing a developer to a development device 221 covering a toner replenishing opening 223a by a seal member 223b having an openable and closable slit 223c includes: a toner feed pipe 73; a toner feed pipe moving mechanism 74; and a shutter control mechanism 75. The toner feed pipe 73 is a member feeding toner to a development unit 221 by passing a toner replenishing opening 223a. The toner feed pipe moving mechanism 74 moves the toner feed pipe 73 to a toner feed position capable of feeding the toner to the development unit 221 and an outside waiting position of the development unit 221. The shutter control mechanism 75 pushes and opens the slit 223c by being contacted on the slit 223c of the seal member 223b before the toner feed pipe 73 when the toner feed pipe 73 passes the seal member 223b. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a developer replenishing device and an image forming apparatus, and in particular, a developer replenishing device and a developer replenishing agent that replenishes a developer from the outside of a developing device in which a developer replenishing port is covered by a seal member formed with a slit The present invention relates to an image forming apparatus including the apparatus.

  An electrophotographic image forming apparatus, such as a copier or a multifunction peripheral, includes a developing device that forms an image on a sheet, a fixing unit that fixes the formed image on the sheet, and the sheet as an image forming unit. Some include a sheet conveying unit that conveys, a discharge unit that discharges a sheet on which an image is fixed, and a developer replenishing device that replenishes the developing device of the image forming unit. In such an image forming apparatus, an image is formed on a sheet by an image forming unit, and the image is fixed on the sheet by a fixing unit. The sheet on which the image is fixed is discharged from the discharge unit. When the developer in the developing device decreases, the developer is replenished to the developing device by the developer replenishing device (see Patent Document 1).

Here, the developing device has a developer supply port covered by a seal member having a slit, and the developer supply device includes a developer storage container provided outside the developing device, and a developer. A device provided with a developer transport member provided in a storage container and a developer supply member for transporting the developer in the developer storage container by the developer transport member is considered. In such an image forming apparatus, when the developer is supplied to the developing device, the developer supply member is inserted into the developer supply port through the slit of the seal member. Then, the developer is supplied from the developer supply member to the developing device.
JP 2002-23472 A

  In such an image forming apparatus, when the developer is supplied from the developer supply member to the developing device, the developer supply member and the seal member slide. For this reason, the load acting on the developer supply member may become unstable. Further, there is a case where a sound called chatter noise is generated with the movement of the developer supply member.

  An object of the present invention is to prevent the load acting on the developer supply member from becoming unstable and chattering from occurring as the developer supply member and the seal member come into sliding contact with each other.

  A developer replenishing device according to claim 1 is a developer replenishing device for replenishing a developer to a developing device in which a developer replenishing port is covered by a seal member having an openable / closable shutter portion, the developer replenishing member And a drive mechanism and a shutter control mechanism. The developer supply member is a member that passes the developer supply port and supplies the developer to the developing device. The drive mechanism moves the developer supply member to a developer supply position where the developer can be supplied to the developing device and a standby position outside the developing device. When the developer supply member passes through the seal member, the shutter control mechanism abuts against the shutter portion of the seal member before the developer supply member and pushes the shutter portion open.

  In this developer supply device, when the amount of developer in the developing device decreases, the drive mechanism moves the developer supply member from the standby position to the developer supply position. At this time, when the developer supply member passes through the seal member, the shutter control mechanism contacts the shutter portion of the seal member before the developer supply member to push the shutter portion open.

  Here, since the developer supply member and the seal member are not in sliding contact with each other, a load is not applied to the developer supply member, and chatter noise can be prevented from being generated.

  A developer supply device according to a second aspect is the developer supply device according to the first aspect, wherein the seal member is formed of an elastically deformable material, and the shutter portion is a slit.

  Here, when the seal member is elastically deformed, the shutter portion is opened, and when the developer supply member is removed from the seal member, the elastic deformation of the seal member is released and the slit is closed.

  A developer replenishing device according to claim 3 is the developer replenishing device according to claim 1 or 2, wherein the shutter control mechanism is provided on an outer peripheral side of the developer supplying member and is movable together with the developer supplying member. And it can move relative to the developer supply member.

here,

The developer supply device according to claim 4 is the developer supply device according to any one of claims 1 to 3, wherein the shutter control mechanism moves relative to the developer supply member after the shutter portion is pushed open. To do.

  Here, since the shutter control mechanism pushes open the shutter portion, and then the developer supply member can be relatively moved, the developer supply member can enter the developing device.

  A developer supply device according to a fifth aspect is the developer supply device according to any one of the first to fourth aspects, wherein the developer supply member has a developer conveyance path through which the developer is conveyed. The front end exit portion of the developer transport path has a shutter mechanism that opens at the developer replenishment position to replenish the developer in the developer transport path to the developing device and closes at a position other than the developer replenishment position.

here,
A developer supply device according to a sixth aspect is the developer supply device according to the fifth aspect, wherein the developer supply member has a developer transport member for transporting the developer to the developer transport path. Yes.

here,
A developer supply device according to a seventh aspect is the developer supply device according to any one of the first to sixth aspects, wherein the developer supply member is a cylindrical member extending in one direction, and the shutter control member is A cylindrical member that houses the developer supply member therein, and has an opening through which the developer supply member can pass.

here,
According to an eighth aspect of the present invention, there is provided a developer replenishing device according to any one of the first to seventh aspects, a developer replenishing device according to any one of the first to seventh aspects, and A developer having a developer replenishing port for replenishing the developer from the developer replenishing device, and a seal disposed in the developing device so as to cover the developer replenishing port and having an openable / closable shutter portion An electrostatic latent image is formed on the surface, a developer is supplied from the developing device, and an electrostatic latent image carrier disposed to face the developing device.

  In this image forming apparatus, an electrostatic latent image is formed on the electrostatic latent image carrier, and a developer is supplied from the developing device onto the electrostatic latent image carrier. At this time, when the developer in the developing device decreases, the developer supply member is moved from the standby position to the supply position by the developer supply member moving mechanism. At this time, the shutter portion of the seal member is pushed open by the shutter control mechanism, and the developer supply member passes through the seal member. Then, the developer is supplied from the developer supply member into the developing device.

  Here, since the developer supply member and the seal member are not in sliding contact with each other, a load is not applied to the developer supply member, and chatter noise can be prevented from being generated.

  In the present invention, it is possible to prevent the load acting on the developer supply member from becoming unstable and the occurrence of chatter noise when the developer supply member and the seal member are in sliding contact with each other.

Configuration FIG. 1 shows a color printer 1 as an image forming apparatus according to an embodiment of the present invention. FIG. 1 is a schematic diagram for illustrating the arrangement of each component, and details of each part are omitted.

  The color printer 1 is connected to a computer (not shown) or the like, and is a device that can print a color image on paper based on image information sent from an external computer or the like. The color printer 1 includes an image forming unit 2, a sheet conveyance path 3, a fixing unit 4, a sheet storage unit 5, a discharge unit 6, and a toner supply device 7 (developer supply device). Here, the toner replenishing device 7 will be described in detail later.

  The image forming unit 2 includes a photosensitive drum 21, a rotary developing device 22, a charging device 23, a laser unit 24, and a cleaning device 25. The rotary developing device 22 will be described in detail later.

  The photosensitive drum 21 is a member on which an electrostatic latent image is formed, and is disposed at the approximate center of the color printer 1. The photosensitive drum 21 is a drum-shaped member, and a rotation shaft is provided in a direction orthogonal to the paper surface of FIG. An intermediate transfer belt 211 for transferring a toner image on the photosensitive drum 21 to a sheet is disposed below the photosensitive drum 21 in the vicinity of the photosensitive drum 21. The charging device 23 is a device for charging the surface of the photosensitive drum 21, and is disposed on the upper side of the photosensitive drum 21.

  The laser unit 24 is a member arranged on the upper side of the rotary developing device 22 and is a portion for irradiating a laser beam to form an electrostatic latent image based on image data on the photosensitive drum 21. It is.

  The cleaning device 25 is a device for removing deposits such as residual toner remaining on the photosensitive drum 21. In the color printer 1, the cleaning is performed on the entire axial direction of the photosensitive drum 21 above the photosensitive drum 21. A blade is provided.

  The paper transport unit 3 has a transport path that continues from the paper storage unit 5 through the image forming unit 2 and the fixing unit 4 to the discharge unit 6.

  The fixing unit 4 is disposed below the rotary developing device 22 and has a heating roller 41 and a pressure roller 42. The heating roller 41 is a member for melting toner that forms an image formed on a sheet by heat, and is disposed on the upper side of the pressure roller 42.

  The paper storage unit 5 is a part disposed at the lower part of the color printer 1 and has a paper feed cassette 51.

  The discharge unit 6 is disposed on the upper surface of the color printer 1 and discharges a sheet on which an image is formed.

2. Rotating Developing Device and Toner Replenishing Device The rotating developing device 22 is a member disposed adjacent to the photosensitive drum 21 and is a cylindrical device as a whole. The rotary developing device 22 includes four developing devices 221 (developing devices) and a frame 222 that supports the four developing devices 221.

  The developing device 221 includes a container body 223 and a developing roller 224. The container body 223 has a shape in which a cylinder is divided into four in the circumferential direction, and has an opening extending in the longitudinal direction. Further, a toner supply port 223a through which a toner supply pipe 73 described later can pass is formed on the surface of the container body 223, and a seal member 223b is disposed so as to cover the toner supply port 223a. The toner supply port 223a is a circular hole having a diameter larger than that of a toner supply pipe 73 described later. The seal member 223b is a substantially square sheet-like elastic member, and a cross-shaped slit 223c (shutter portion) is formed at substantially the center. The periphery of the seal member 223b (contact portion with the developing unit 221) is formed in a bellows shape (see FIG. 6), and the periphery of the slit 223c is thick. The four container main bodies 223 store yellow, cyan, magenta, and black toners, respectively.

  The developing roller 224 extends in the rotation axis direction of the rotary developing device 22 and is disposed in the opening of the container main body 223. The developing roller 224 is a member for supplying toner to the surface of the photosensitive drum 21. At both ends of the developing roller 224, distance regulating rollers 225 for maintaining a distance between the photosensitive drum 21 and the developing roller 224 are disposed. The distance regulating roller 225 is a disk-like member having a larger radius than the developing roller 224, and keeps the distance between the photosensitive drum 21 and the developing roller 224 constant.

  As shown in FIGS. 1, 3, and 4, the toner replenishing device 7 is for replenishing toner to the developing device 221, and includes a toner container 71 (developer storage container) and a toner transport pipe 72 (developer). A conveyance member), a toner supply pipe 73 (developer supply member), a toner supply pipe moving mechanism 74 (drive mechanism), and a shutter control mechanism 75 (see FIGS. 6 to 8). Here, FIG. 3 shows a seal member 223b and the like provided in the developing unit 221. Further, the toner replenishing device 7 is disposed above the photosensitive drum 21 at substantially the same height as the laser unit 24. The toner transport pipe 72 is a flexible pipe so that it can move following the vertical movement of the toner supply pipe 73. A coil spring 721 is disposed inside and rotated by a driving mechanism (not shown), whereby the toner is conveyed to the toner supply pipe 73 side through the toner conveyance pipe 72. The toner supply pipe 73 is long in the vertical direction, and the upper end is inclined to the right side in FIG. 1 and the lower end is inclined to the left side in FIG. In addition, an opening for supplying toner is provided at the tip of the toner supply pipe 73. The toner supply pipe 73 has a tapered tip, and when it moves downward, the tip enters the interior through a slit 223c formed in a seal member 223b disposed on the surface of the developing unit 221. Is possible. A toner conveying screw 731 is rotatably provided inside the toner supply pipe 73. Further, two guide projections 732c (see FIG. 6) projecting outward are provided at the lower portion of the toner supply pipe 73.

  As shown in FIGS. 2 and 4, the toner supply pipe moving mechanism 74 has a rack 741 provided along the axial direction on the outer periphery of the toner supply pipe 73, and a pinion gear 742 that meshes with the rack 741. ing. The pinion gear 742 is rotatably supported by the frame of the apparatus, and is driven by a motor 743, a worm, a worm wheel, and a reduction gear train. Then, the toner supply pipe moving mechanism 74 allows the four toner supply pipes 73 to take the upper retracted position and the lower supply position where the tip portion has entered the inside of the developing device 221. Here, FIG. 2 is a diagram showing the toner transport pipe 72, the toner supply pipe 73, and the like.

  The toner supply pipe 73 has a shutter mechanism 744 that opens only when the toner supply pipe 73 is located at the supply position. As shown in FIG. 5, in the shutter mechanism 744, an inner cylinder 744a disposed inside the toner supply pipe 73 and having an opening at the tip rotates with respect to the toner supply pipe 73. When the opening of 744a overlaps, it is configured to open. Here, FIG. 5 shows the shutter mechanism 744.

  The shutter control mechanism 75 is a mechanism that abuts against the slit 223c of the seal member 223b before the toner supply pipe 73 and pushes the slit 223c open when the toner supply pipe 73 passes, as shown in FIG. An urging member 751 and a cylindrical member 752 are provided. The biasing member 751 is a member that is disposed between the cylindrical member 752 and the toner supply pipe 73 and biases the cylindrical member 752 downward in FIG. The cylindrical member 752 is a part that contacts the seal member 223b at the lower end of FIG. 6, and includes a disk-shaped part 752a, a cylindrical part 752b, and a guide part 752c. The disc-shaped portion 752a is connected to the urging member 751, and a circular large hole 752d (see FIG. 6) through which the toner supply pipe 73 can pass is disposed in the center, and 2 on the outer peripheral side of the central large hole 752d. Two small holes (not shown) are provided. Two protrusions 223d (see FIG. 6) formed on the frame of the color printer 1 are inserted into these two small holes. When the two protrusions 223d formed on the frame are inserted into the small holes, the disk-shaped portion 752a cannot be rotated relative to the frame. The cylindrical part 752b is provided on the outer peripheral side of the large hole 752d, and the disk-like part 752a is urged by the urging member 751 and is located on the lowermost side of FIG. The tip is located at the same height as the tip of the toner supply pipe 73. Moreover, the lower end of FIG. 6 of the cylindrical part 752b has a tapered shape. The guide portion 752c is provided on the inner peripheral side of the cylindrical portion 752b and is formed in a spiral shape. A guide protrusion 732c of the toner supply pipe 73 is engaged with the guide portion 752c, and the guide protrusion 732c is guided as the toner supply pipe 73 is lowered to the lower side in FIG. Let

3. Operation An image forming operation will be described.

  When image information is transmitted from a computer connected to the outside, the surface of the photosensitive drum 21 is charged by the charging device 23 and irradiated from the irradiation device based on the image information. When an electrostatic latent image is formed on the photosensitive drum 21, the frame 222 rotates and toner is supplied from each developing device 221 to the photosensitive drum 21. When an image is formed on the photosensitive drum 21 in this way, the image is transferred onto a sheet via the intermediate transfer belt 211. The sheet onto which the image has been transferred is conveyed to the fixing unit 4 where the image is fixed. Thereafter, the paper is discharged from the discharge unit 6 to the outside of the color printer 1.

  Next, an operation of supplying toner when the toner in the developing device 221 is reduced will be described.

  When the toner in the developing device 221 decreases, the pinion gear 742 is rotated by the power of the motor 743, and the toner supply pipe 73 moves downward in FIG. 6 as the pinion gear 742 rotates. At this time, the projection 223d of the color printer 1 is inserted into the small hole of the disk-like portion 752a, and the cylindrical member 752 becomes non-rotatable (see FIG. 7). Further, when the toner supply pipe 73 moves downward in FIG. 6 against the urging force of the urging member 751, the guide protrusion 732c of the toner supply pipe 73 is guided by the guide portion 752c of the cylindrical member 752 and rotates. Be made. When the toner supply pipe 73 rotates, the opening of the toner supply pipe 73 and the opening of the inner cylinder overlap with each other so that toner can be supplied from the toner supply pipe 73 (see FIG. 8). At this time, the coil spring 721 in the toner transport pipe 72 is driven, and the toner is transported from the toner container 71 to the toner supply pipe 73 side. Then, the toner conveying screw 731 inside the toner supply pipe 73 rotates to convey the toner to the opening. In this way, the toner in the toner container 71 is supplied to the developing device 221. Here, in a state where the toner supply pipe 73 is moved downward in FIG. 6 and the protrusion 223d of the color printer 1 is inserted into the small hole, the lower end of the cylindrical member 752 in FIG. 6 is shown in FIG. As described above, when the toner supply pipe 73 passes through the slit 223c in contact with the vicinity of the slit 223c of the seal member 223b, the slit 223c is pushed open by contacting the slit 223c of the seal member 223b before the toner supply pipe 73. It is done. 7 is a view showing a state where the cylindrical member 752 and the seal member 223b are in contact with each other, and FIG. 8 is a view showing a state where the toner supply pipe 73 is located at the supply position.

  Here, the chatter noise generated when the toner supply pipe 73 and the seal member 223b are slidably contacted with each other without the toner supply pipe 73 and the seal member 223c being in contact with each other can be prevented. Further, the toner supply pipe 73 is not subjected to a load by the seal member 223b, and the load acting on the toner supply pipe 73 can be prevented from becoming unstable.

4). Other Embodiments (a) Although the color printer 1 has been described in the above embodiment, the present invention is not limited to this, and may be a copying machine, a multifunction machine, or the like.

  (B) In the above embodiment, the slit 223c of the seal member 223b is a cross, but the present invention is not limited to this, and may be a single slit, or a plurality of slits may be radial. You may form in.

1 is a schematic diagram of a color printer 1. FIG. The figure which shows a toner supply pipe, a toner conveyance pipe, etc. FIG. 3 is a diagram illustrating a toner supply port of a developing device 221. FIG. 4 is a diagram illustrating a toner supply pipe moving mechanism. FIG. 4 is a diagram illustrating a shutter mechanism of a toner supply pipe. FIG. 6 is a diagram illustrating a state where the toner supply pipe is in a standby position. The figure which shows the state which the front-end | tip of a cylindrical member is contact | abutting to the sealing member. FIG. 6 is a diagram illustrating a state where the toner supply pipe is located at a supply position.

Explanation of symbols

1 Color printer (image forming device)
7 Toner supply device (Developer supply device)
21 Photosensitive drum (electrostatic latent image carrier)
71 Toner container (developer storage container)
72 Toner transport pipe (developer transport member)
73 Toner Supply Pipe (Developer Supply Member)
74 Toner supply pipe moving mechanism (developer supply member moving mechanism)
75 Shutter control mechanism 221 Developing device (developing device)
223a Toner supply port (developer supply port)
223b Seal member 223c Slit (shutter part)
224 Developing roller 744 Shutter mechanism

Claims (8)

A developer replenishing device for replenishing a developer to a developing device whose developer replenishing port is covered by a seal member having a shutter part that can be freely opened and closed,
A developer supply member that passes through the developer supply port and supplies the developer to the developing device;
A drive mechanism for moving the developer supply member to a developer supply position capable of supplying the developer to the developing device and a standby position outside the developing device;
A shutter control mechanism that, when the developer supply member passes through the seal member, contacts the shutter portion of the seal member before the developer supply member to push the shutter portion open;
A developer replenishing device. The seal member is made of an elastically deformable material,
The shutter part is a slit,
The developer replenishing device according to claim 1.   3. The developer supply device according to claim 2, wherein the shutter control mechanism is provided on an outer peripheral side of the developer supply member, and is movable with the developer supply member and relatively movable with the developer supply member.   The developer supply device according to claim 3, wherein the shutter control mechanism moves relative to the developer supply member after the shutter portion is pushed open.   The developer supply member includes a developer transport path through which the developer is transported, and is opened at the developer replenishment position at a front end outlet portion of the developer transport path so as to be within the developer transport path. 5. The developer replenishing device according to claim 1, further comprising a shutter mechanism that replenishes the developing device with a developer and closes the developer at a position other than the developer replenishing position.   The developer supply device according to claim 5, wherein the developer supply member includes a developer transport member for transporting the developer to the developer transport path. The developer supply member is a cylindrical member extending in one direction,
The shutter control member is a cylindrical member that houses the developer supply member therein, and has an opening through which the developer supply member can pass.
The developer replenishing device according to claim 1. A developer replenishing device according to any one of claims 1 to 7,
When the developer decreases, the developer is replenished from the developer replenishing device, and the developing device having a developer replenishing port for replenishing the developer;
A seal member disposed in the developing device so as to cover the developer replenishing port, and having a shutter part that can be freely opened and closed;
An electrostatic latent image is formed on the surface, a developer is supplied from the developing device, and the electrostatic latent image carrier disposed to face the developing device;
An image forming apparatus.

Images