JP5194389B2 - Toner cartridge and developing device - Google Patents

Description

  The present invention relates to a toner cartridge and a developing device used in an electrophotographic image forming apparatus.

  2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus, a toner cartridge including a toner container and a process cartridge in which the toner container is accommodated integrally with a photosensitive drum, a developing device, and the like are used. A rotating member for conveying or stirring the toner is provided inside the toner container, and the rotating member is supported by a bearing attached to the housing of the toner container.

  Further, a filling port for filling toner is provided on the side surface of the end of the toner container. The toner filling time can be shortened as the diameter of the filling port is increased. That is, productivity is improved. On the other hand, a bearing for the rotating member is also arranged on the side surface of the end portion of the toner container. For this reason, there is a restriction on increasing the diameter of the filling port. In recent years, the size of the toner container has been reduced, and this restriction has become remarkable. In other words, there is a trade-off between improving productivity and downsizing.

As a toner container focusing on this problem, for example, as disclosed in Patent Document 1, a bearing member of a rotating member is fitted into a housing of the toner container, and a toner filling port is provided in the bearing member. What has been proposed. For example, Patent Document 2 proposes a method in which a bearing portion is provided in a housing of a toner container, an opening is provided around the bearing portion, and toner is charged from the opening. In these toner containers, a filling port is arranged so as to surround the bearing. By arranging in this way, it is possible to achieve both improvement in productivity and downsizing.
Japanese Patent Laid-Open No. 7-28317 Japanese Patent No. 2704959

  However, the prior art described above has the following problems. That is, when toner is filled in the state where the bearing of the rotating member exists at the center of the filling port, a part of the toner collides with the bearing and the bearing rib and is reflected. The reflected toner spills out of the toner container, wastes the toner and contaminates the operator.

  The present invention has been made to solve the problems of the toner cartridge or developing device having the conventional toner container. That is, an object of the present invention is to provide a toner cartridge and a developing device that achieve both improvement in productivity and downsizing while suppressing toner spillage during toner filling.

A toner cartridge made for the purpose of solving this problem is a toner cartridge that includes a toner container that contains toner and is detachable from an image forming apparatus, and at least one end of the toner cartridge is housed in the toner container. A rotating member that rotates about a rotation axis, a toner filling port that is provided on a side surface of the toner container that constitutes one side surface in the longitudinal direction , and that allows toner to be filled in the toner container; located within container, from the side surface of the toner container with a predetermined interval in the longitudinal direction of the toner container is disposed opposite to the side surface portion, and a bearing member for supporting the rotation shaft of the rotary member, the side surface portion of the toner container An inclined portion formed below the toner filling port and formed with an inclined surface inclined toward the bearing member on the inner surface of the toner container, and on the longitudinal direction of the toner container. , And an auxiliary toner accommodating portion that is located between the bearing member and the toner filling port and the inclined portion and serves as a toner accommodating space.

  In the toner cartridge of the present invention, at least one end of the rotating member is completely accommodated in the toner container, and a bearing member that supports the rotating shaft is located in the toner container. That is, at least one of the bearings is not located on the housing of the toner container. Therefore, the toner filling port located in the housing of the toner container is not restricted by the arrangement of the bearing. Therefore, the diameter of the toner filling port can be increased, and the toner filling time can be shortened. Further, the toner container can be reduced in size while the toner filling port has a large diameter. Therefore, both improvement in productivity and downsizing can be achieved.

  Further, the bearing member in the toner container is disposed to face the toner filling port with a predetermined gap. That is, in the toner container, in addition to the toner container that stores the toner, an auxiliary toner container formed by a gap between the bearing member and the toner filling port is formed upstream of the bearing member in the toner supply direction. Is done. In the toner cartridge of the present invention, when the toner is filled, a part of the toner collides with the bearing member located in the toner container and is reflected. However, the reflected toner is accommodated in an auxiliary toner accommodating portion formed between the bearing member and the toner filling port without spilling outside the toner container. Therefore, contamination during toner filling is suppressed.

Further, it is preferable that an inclined surface inclined toward the bearing member is formed on the inner wall surface of the side surface of the end portion of the toner container and below the toner filling port. By providing such an inclined surface, the toner reflected on the bearing member and dropped into the auxiliary toner accommodating portion moves to the bearing member side along the inclined surface, and is carried from the auxiliary toner accommodating portion into the toner accommodating portion. Therefore, the toner colliding with the bearing member can be used, and the toner is not wasted.

  Further, it is better that the bearing member holds the rotating shaft of the rotating member on three surfaces. That is, the contact area with the rotating shaft can be reduced by supporting the rotating shaft with the three surfaces that are the minimum configuration. Therefore, heat generation is suppressed. Moreover, if it supports on 3 surfaces, a clearance gap will arise between a bearing member and a rotating shaft. Therefore, the toner flow is good.

  The width of the rib supporting the bearing member is preferably narrower toward the upstream side in the toner supply direction. With such a shape, the collision surface with the toner is not orthogonal to the toner supply direction. Therefore, the scattering of the toner colliding with the bearing member to the toner filling port side can be reduced.

According to another aspect of the present invention, there is provided a developing device that is mounted in an image forming apparatus and that develops an electrostatic latent image formed on an image carrier, the toner container containing toner, and at least one end thereof. A toner that is accommodated in the toner container and rotates around the rotation axis, and a toner filling that is located on the side surface of one end of the toner container in the longitudinal direction and allows toner to be filled in the toner container. A bearing member positioned in the toner container and facing the end side surface at a predetermined interval in the longitudinal direction of the toner container from the end side surface of the toner container and supporting the rotating shaft of the rotating member And a developing device characterized in that it has an auxiliary toner storage portion that is located between the bearing member and the side surface of the end portion of the toner container and serves as a toner storage space .

  According to the present invention, a toner cartridge and a developing device that achieve both improvement in productivity and size reduction while suppressing toner spillage during toner filling are realized.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below in detail with reference to the accompanying drawings. In this embodiment, the present invention is applied to a developing device integrated with a toner container. In the embodiment, the present invention is applied to the developing device, but it goes without saying that the present invention can also be applied to a toner cartridge and a process cartridge.

  As shown in FIG. 1, the image forming apparatus 100 according to this embodiment includes a photosensitive drum 11 that is an image carrier, and uniformly charges the surface of the photosensitive drum 11 around the photosensitive drum 11. A charging device 12, an exposure device 13 for forming an electrostatic latent image on the surface of the photosensitive drum 11, and an electrostatic latent image on the photosensitive drum 11 for making a visible image (toner image). A developing device 14, a transfer device 15 for transferring the toner image on the photosensitive drum 11 to a sheet, and a cleaning device 16 for removing the transfer residual toner from the photosensitive drum 11 are arranged in the rotation direction of the photosensitive drum 11. Along with. Further, a timing roller 17 for adjusting the timing of conveying the sheet to the transfer position and a fixing device 18 for fixing the transferred toner image on the sheet are provided in the sheet conveying path. In this embodiment, the charging device 12, the transfer device 15, and the fixing device 18 are all roller type. The cleaning device 16 uses a cleaning blade.

  Next, an image forming operation by the image forming apparatus 100 will be briefly described. The image forming apparatus 100 starts operation by receiving a start signal, image data, and the like. The photosensitive drum 11 is rotationally driven in the direction of the arrow in FIG. Then, it is uniformly charged by the charging roller at a position facing the charging device 12. Next, exposure is performed by the exposure device 13, and an electrostatic latent image based on the image data is formed on the surface.

  Next, when the electrostatic latent image reaches the position of the developing device 14, the toner charged by the electric field formed between the developing bias voltage applied to the developing roller and the electrostatic latent image on the photosensitive drum 11 moves. Then, the electrostatic latent image is developed with toner.

  On the other hand, the paper transported through the paper transport path is timed by the timing roller 17 to the front end position of the image, and is transported between the photosensitive drum 11 and the transfer device 15. Then, the toner image on the photosensitive drum 11 is transferred to a sheet by the transfer device 15. Further, the sheet holding the transferred toner image is further conveyed, and heat and pressure are applied by the fixing device 18 to fix the toner image on the sheet. Further, the transfer residual toner which is not transferred onto the sheet by the transfer device 15 and remains on the photosensitive drum 11 is scraped off by the cleaning device 16. Thereby, the image formation for one sheet is completed.

  Next, the developing device 14 will be described in detail. In the developing device 14, a driving force is transmitted to one side in the longitudinal direction. Therefore, in this specification, the side on which the driving force is obtained is referred to as “driving side”, and the opposite side is referred to as “counter driving side”. FIG. 2 is a perspective view of the developing device 14 as viewed from the driving side. FIG. 3 is a perspective view of the developing device 14 as viewed from the non-driving side. 2 and 3 also show the photosensitive drum 11 in addition to the developing device 14.

  The developing device 14 includes a developing roller 2, rollers 31 and 32 positioned at both ends in the longitudinal direction of the developing roller 2, and a rotation support shaft 6 that engages with the main body of the image forming apparatus 100. The rollers 31 and 32 are spacer members that keep the surface distance between the developing roller 2 and the photosensitive drum 11 constant. The roller 31 and the roller 32 are inserted on the shaft of the developing roller 2 and are rotatably provided with the developing roller 2. In the present embodiment, the roller on the driving side is the roller 31 and the roller on the non-driving side is the roller 32. A driven gear (not shown) is provided on the driving side surface of the developing device 14 and meshes with the driving gear of the image forming apparatus main body to transmit the driving force from the driving gear to the developing roller 2.

  Further, the developing device 14 is provided so as to be rotatable around a rotation support shaft 6 that engages with a support portion of the image forming apparatus main body. Then, it rotates to the photosensitive drum 11 side, and the developing roller 2 is fixed to the main body of the image forming apparatus 100 with the developing roller 2 facing the photosensitive drum 11. That is, the developing roller 2 and the photosensitive drum 11 face each other with the rollers 31 and 32 therebetween. Further, the developing device 14 is urged toward the photosensitive drum 11 by a pressing spring provided in the image forming apparatus main body.

  Further, a toner filling port 4 is provided on the side surface of the developing device 14 on the side opposite to the driving side (FIG. 3). When the developing device 14 is produced, the toner is filled from the toner filling port 4. After the toner is filled, a cap 40 that prevents toner leakage is attached. FIG. 3 illustrates a state where the cap 40 is attached.

  FIG. 4 is a cross-sectional view of the developing device 14 as viewed from the non-driving side. The developing device 14 includes a toner container 20 that stores non-magnetic toner that is a one-component developer, a developing roller 2 that carries the toner and conveys the toner toward the photosensitive drum 11, and toner to the developing roller 2. Toner supply roller 23 for supplying toner and scraping off the toner on the developing roller 2, toner amount regulating members 241 and 242 for regulating the thickness of the toner on the developing roller 2, and a developing roller for preventing toner leakage and after development 2 is provided with a toner neutralizing member 25 that neutralizes the toner remaining on the sheet 2 and screws 261 and 262 that convey the toner in the longitudinal direction of the developing device 14. In addition, the toner storage unit 20 includes a housing 21 that constitutes a tank that stores toner, and a stirring member 22 that rotates around a rotation shaft 220 to stir the toner in the tank. The various rotating members rotate by obtaining a driving force from the driving gear of the image forming apparatus main body. Further, a power source is connected to the developing roller 2 and a bias for development is applied.

  In the developing device 14, the toner is conveyed from the toner supply roller 23 to the developing roller 2 by the potential difference between the toner supply roller 23 and the developing roller 2 and the mechanical conveying force of the toner supply roller 23 whose surface is foam. The toner supplied to the developing roller 2 is thinned while being frictionally charged by the toner amount regulating members 241 and 242 as the developing roller 2 rotates, and an electrostatic latent image is formed at a portion facing the photosensitive drum 11. Visualize.

  FIG. 5 is a side view of the developing device 14 as viewed from the non-driving side. 6 is a perspective top perspective view of the periphery of the side opposite to the driving side of the toner storage unit 20. FIG. Further, FIG. 7 is a cross-sectional view showing a cross section A of the toner container 20 shown in FIG. 5 shows a state where the cap 40 of the toner filling port 4 is removed, and FIG. 6 shows a state where the cap 40 is attached.

  As shown in FIG. 5, a toner filling port 4 that is used when filling the toner is provided on the side surface of the housing 21 opposite to the driving side. Further, as shown in FIGS. 6 to 7, the toner accommodating portion 20 formed in the housing 21 is provided with a bearing member 5 that supports the rotating shaft 220. Further, the end of the rotating shaft 220 on the side opposite to the driving side is located inside the housing 21 and is supported by the bearing member 5. On the other hand, an end (not shown) on the drive side is located outside the housing 21 and transmits driving force.

  Further, the bearing member 5 is disposed opposite to the side surface of the housing 21 opposite to the driving side with a predetermined interval, and an auxiliary toner accommodating portion 200 is formed between the side surface and the bearing member 5. At the time of toner filling, toner is sent from the toner filling port 4 to the toner container 20 via the auxiliary toner container 200.

  The bearing member 5 is disposed inside the housing 21, and the end of the rotating shaft 220 on the side opposite to the driving side (that is, the side where the toner filling port 4 is formed) is completely accommodated in the toner accommodating portion 20. ing. For this reason, the toner filling port 4 is not restricted by the arrangement of the bearing member 5 and can have a large diameter. Therefore, the toner filling time can be shortened. Further, even if the volume of the toner containing portion 20 is reduced, that is, the area of the cross section perpendicular to the longitudinal direction of the toner containing portion 20 is reduced, the arrangement of the bearing member 5 does not prevent the toner filling port 4 from increasing in diameter. Absent. Therefore, both improvement in productivity and downsizing can be achieved.

  Further, the bearing member 5 is disposed at a predetermined interval so that the auxiliary toner accommodating portion 200 is provided between the bearing member 5 and the toner filling port 4. For this reason, even if the toner carried from the toner filling port 4 collides with the bearing member 5 and is reflected, the reflected toner falls into the auxiliary toner accommodating portion 200. Therefore, the toner can be filled without spilling the toner to the outside.

  In addition, an inclined surface 211 that is inclined toward the bearing member 5 (that is, inside the housing 21) is provided below the toner filling port 4 on the side opposite to the driving side of the housing 21, as shown in FIG. ing. Due to the inclined surface 211, the distance between the side surface of the housing 21 and the bearing member 5 becomes narrower toward the lower side in the auxiliary toner accommodating portion 200 below the toner filling port 4.

  When the toner is filled, the toner that collides and is reflected by the bearing member 5 moves to the bearing member 5 side along the inclined surface 211. Then, it is carried into the toner storage portion 20 through the opening 55 positioned below the bearing member 5. Therefore, the toner colliding / reflecting the bearing member 5 can be used, and the toner is not wasted.

  As shown in FIG. 8, the bearing member 5 includes a frame portion 50, a bearing portion 51 that supports the rotary shaft 220 in a slidable manner, and a bearing rib 52 that fixes the bearing portion 51 to the frame portion 50. . Furthermore, several through holes 55 defined by the bearing portion 51 and the bearing rib 52 are provided in the frame portion 50. The toner fed from the toner filling port 4 passes through the through hole 55 and is supplied into the toner containing portion 20 without being blocked by the bearing member 5.

  As shown in FIG. 8, the bearing portion 51 has a shape that supports the rotating shaft 220 on three surfaces. The bearing sliding member 51 may have a shape that is held by three surfaces, and may have a configuration in which the opening that accommodates the rotating shaft 220 has a triangular shape as in the present embodiment (FIG. 9A). For example, as shown in FIG. 9B, the opening may have a hexagonal shape. Or the structure (FIG.9 (c)) hold | maintained by three support parts may be sufficient. Since the bearing portion 51 has a shape that supports the rotating shaft 220 on three surfaces, the contact area with the rotating shaft 220 is small compared to other configurations that support on four or more surfaces. Therefore, heat generation is suppressed. Further, if only three surfaces are supported, many gaps are generated between the bearing portion 51 and the rotating shaft 220. Therefore, the toner flow is good.

  FIG. 10A shows a BB cross section of the bearing member shown in FIG. As shown in FIG. 10, the bearing rib 52 has a shape in which the width becomes narrower toward the upstream side in the toner supply direction. That is, the toner collision surface is not orthogonal to the toner supply direction. Therefore, scattering of the toner that collides with and is reflected by the bearing member 5 toward the toner filling port 4 can be reduced. If the width of the bearing rib 52 is narrower toward the upstream side in the toner supply direction, there is an effect of reducing the scattering of the toner. For example, the bearing rib 52 has a shape as shown in FIGS. 10B and 10C. Also good.

  Note that the shape of the frame portion 50 and the bearing portion 51, the arrangement and number of the bearing ribs 52, and the like vary depending on the shape of the housing 21 and the mechanical strength required for the bearing member 5, and are not limited to this embodiment.

  As described above in detail, in the developing device 14 of this embodiment, the end of the stirring member 22 on the side opposite to the driving side is accommodated in the housing 21, and the bearing member 5 that supports the rotating shaft 220 of the stirring member 22 is provided in the housing 21. 21. That is, the bearing member 5 that supports the end of the rotating shaft 220 on the non-driving side is not provided in the housing 21. Therefore, the toner filling port 4 is not restricted by the arrangement of the bearing member 5. Therefore, the diameter of the toner filling port 4 can be increased, and the toner filling time can be shortened. Even if the housing 21 is reduced in size, the arrangement of the bearings does not hinder the increase in the diameter of the toner filling port 4. Therefore, both improvement in productivity and downsizing can be achieved.

  Further, the bearing member 5 is disposed to face the toner filling port 4 with a predetermined gap. That is, in the housing 21, in addition to the toner storage portion 20 that stores toner, auxiliary toner storage that is formed by a gap between the bearing member 5 and the toner filling port 4 upstream of the bearing member 5 in the toner supply direction. Part 200 is provided. Then, the toner that collides and is reflected by the bearing member 5 during toner filling is accommodated in the auxiliary toner accommodating portion 200 formed between the bearing member 5 and the toner filling port 4 without spilling outside the housing 21. Is done. Therefore, contamination during toner filling is suppressed. Therefore, a developing device that achieves both improvement in productivity and miniaturization while suppressing toner spillage during toner filling has been realized.

  Note that this embodiment is merely an example, and does not limit the present invention. Therefore, the present invention can naturally be improved and modified in various ways without departing from the gist thereof. For example, the present invention can be applied to various image forming apparatuses such as a color printer, a monochrome printer, a copier, and a facsimile. Further, the developing method is not limited to the one-component developing method, and a two-component developing method is also applicable.

  Further, although a roller-shaped photosensitive drum is used as the image carrier, a belt-shaped photosensitive belt may be used. In addition to the roller charging method, the charging device may use a corona discharge charging charger, blade, brush, or the like. The exposure apparatus may be a laser or LED. The transfer device may use a transfer charger in addition to the transfer roller. Alternatively, in addition to a method of directly transferring a toner image from a photosensitive member to a sheet, a method of providing an intermediate transfer member and performing transfer in two or more stages may be used. In addition to the cleaning blade, the cleaning device may be a cleaning brush, a cleaning roller, or a combination thereof. Alternatively, the transfer residual toner may be collected by a developing device. In addition to the fixing roller, the fixing device may use a fixing belt or a non-contact type.

1 is a diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment. 1 is a perspective view (drive side) showing an overall configuration of a developing device according to an embodiment; 1 is a perspective view (reverse drive side) showing an overall configuration of a developing device according to an embodiment; 1 is a cross-sectional view illustrating an overall configuration of a developing device according to an embodiment. It is a side view (counter drive side) which shows the whole structure of the developing device concerning an embodiment. FIG. 6 is a top perspective view illustrating a configuration of a toner storage portion of the developing device. FIG. 6 is a cross-sectional view illustrating a cross section A of the toner storage unit illustrated in FIG. 5. It is a figure which shows schematic structure of the bearing member concerning embodiment. It is a figure which shows the example of a shape of the bearing sliding part of a bearing member. It is sectional drawing which shows the BB cross section of the bearing member shown in FIG.

Explanation of symbols

2 Developing roller 4 Toner filling port 5 Bearing member 11 Photosensitive drum 14 Developing device 20 Toner accommodating portion 21 Housing 22 Stirring member (rotating member)
40 Cap 100 Image forming apparatus 200 Auxiliary toner accommodating portion 211 Inclined surface 220 Rotating shaft

Claims (8)

In a toner cartridge having a toner container for containing toner and detachable from an image forming apparatus,
A rotating member having at least one end accommodated in the toner container and rotating about a rotation axis;
A toner filling port which is provided on a side surface portion constituting one side surface in the longitudinal direction of the toner container and allows toner to be filled in the toner container;
A bearing member located in the toner container, disposed opposite the side surface portion at a predetermined interval in the longitudinal direction of the toner container from the side surface portion of the toner container, and supporting a rotating shaft of the rotating member; ,
An inclined portion that is a part of the side surface portion of the toner container, is located below the toner filling port, and an inclined surface that is inclined toward the bearing member is formed on the inner surface of the toner container When,
An auxiliary toner storage portion that is located between the bearing member, the toner filling port, and the inclined portion on the longitudinal direction of the toner container and serves as a toner storage space;
A toner cartridge comprising: The toner cartridge according to claim 1,
An end of the rotating member on the toner filling port side is located in the toner container. In the toner cartridge according to claim 1 or 2 ,
The toner cartridge, wherein the bearing member holds a rotating shaft of the rotating member on three surfaces. The toner cartridge according to any one of claims 1 to 3 , wherein
2. A toner cartridge according to claim 1, wherein the width of the rib supporting the bearing member is narrower toward the upstream side in the toner supply direction. In a developing device that is mounted in an image forming apparatus and develops an electrostatic latent image formed on an image carrier,
A toner container for containing toner;
A rotating member having at least one end accommodated in the toner container and rotating about a rotation axis;
A toner filling port which is provided on a side surface portion constituting one side surface in the longitudinal direction of the toner container and allows toner to be filled in the toner container;
A bearing member located in the toner container, disposed opposite the side surface portion at a predetermined interval in the longitudinal direction of the toner container from the side surface portion of the toner container, and supporting a rotating shaft of the rotating member; ,
An inclined portion that is a part of the side surface portion of the toner container, is located below the toner filling port, and an inclined surface that is inclined toward the bearing member is formed on the inner surface of the toner container When,
An auxiliary toner storage portion that is located between the bearing member, the toner filling port, and the inclined portion on the longitudinal direction of the toner container and serves as a toner storage space;
A developing device comprising: The developing device according to claim 5 ,
An end of the rotating member on the toner filling port side is located in the toner container. In the developing device according to claim 5 or 6 ,
The developing device according to claim 1, wherein the bearing member holds a rotating shaft of the rotating member on three surfaces. In the developing device according to any one of claims 5 to 7 ,
2. A developing device according to claim 1, wherein a width of the rib supporting the bearing member is narrower toward an upstream side in a toner supply direction.

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