JP5534339B2 - Toner supply device and image forming apparatus - Google Patents

Description

  The present invention relates to a toner replenishing device for replenishing toner contained in a toner container to a developing device, and an image forming apparatus including the toner replenishing device.

  Conventionally, in an image forming apparatus using an electrophotographic method such as a copying machine, a printer, a facsimile, or a composite machine thereof, the toner contained in the toner container is developed at a position away from the toner container. 2. Description of the Related Art Toner replenishing devices (toner transporting devices) that transport and replenish toward an apparatus are known (see, for example, Patent Documents 1 and 2).

  In Patent Documents 1 and 2 and the like, a toner container (toner bottle) containing toner is detachably (replaceable) with respect to the main body of the image forming apparatus, and a developing device (process) is located away from the toner container. Cartridge). A toner replenishing device (toner conveying device) is disposed so as to relay between the toner container and the developing device. The toner replenishing device includes a toner tank unit (sub hopper) that stores toner discharged from a toner container, and a toner transport pipe (toner transport pipe) that transports toner stored in the toner tank unit toward a developing device (process cartridge). ), Etc. The toner transport tube transports toner from the toner tank portion and replenishes the developing device with toner, and a screw member (toner transport screw, transport coil) is provided therein.

Then, according to the consumption of the toner in the developer contained in the developing device (the toner consumption associated with the developing process), the screw member is controlled to be turned on / off for a predetermined time, so that the toner is directed toward the developing device. Is replenished as appropriate.
The image forming apparatus configured as described above is known as an apparatus that has a high degree of freedom in layout and can be miniaturized because it is not necessary to dispose the toner container and the developing device close to each other.

In the conventional toner replenishing device, the load applied to the drive unit that drives the screw member changes, and the drive time (or the amount of rotation per unit time) for the screw member to make one rotation changes. In some cases, the amount of toner supplied to the apparatus varies. In particular, in a toner replenishing device configured to drive a toner container having a large variation in driving torque by a driving unit that drives a screw member, a load variation in the driving unit becomes large, which is a problem that cannot be ignored. It was.
When a larger amount of toner than the target toner amount is replenished in the developing device, the toner concentration of the developer in the developing device (the ratio of the toner in the developer) becomes higher than the target. As a result, the image density of the output image increases, or the toner charge amount decreases, causing toner scattering and a background smear image. On the other hand, when toner smaller than the target toner amount is supplied into the developing device, the toner concentration of the developer in the developing device becomes lower than the target, and the image density of the output image is low. Or the carrier adhered to the image carrier or the output image.

  The present invention has been made to solve the above-described problems, and even when the load applied to the drive unit that drives the screw member changes, the amount of toner supplied to the developing device is less likely to vary. To provide a toner replenishing device and an image forming apparatus.

  As a result of repeated research to solve the above problems, the inventor of the present application contacts the detection surface of the detection means that detects that the amount of toner stored in the toner tank portion has become a predetermined amount or less and cleans the detection surface. When the rotation shaft on which the flexible member to be rotated is rotationally driven by the drive unit that drives the screw member, the drive time for one rotation of the screw member is indirectly obtained from the cycle of the output fluctuation of the detection means. I learned that I can.

  The present invention is based on the matters described above, that is, the toner replenishing device according to the first aspect of the present invention is a toner replenishing device for replenishing the developing device with the toner contained in the toner container. The toner tank unit storing the toner discharged from the toner container and the inner wall of the toner conveyance tube communicating with the toner tank unit are rotated in a predetermined direction by a driving force input from the driving unit. A screw member that conveys the toner stored in the toner tank unit, wherein the toner tank unit detects that the amount of toner stored therein is below a predetermined amount, and the drive unit The detection surface of the detection means comes into contact with the cleaning surface while rotating together with the rotary shaft that is driven to rotate in a predetermined direction by the driving force input from the A driving time for one rotation of the screw member based on the output fluctuation period of the detection surface, and drive control of the screw member based on the driving time for one rotation. Make adjustments.

  According to a second aspect of the present invention, there is provided the toner replenishing device according to the first aspect of the present invention, wherein the rotation period in which the flexible member contacts the detection surface is the output fluctuation period of the detection means. From the rotation period, the drive time for one rotation of the screw member is obtained.

  According to a third aspect of the present invention, there is provided the toner replenishing device according to the first or second aspect, wherein the driving time for one rotation determined from the output fluctuation period of the detecting means is predetermined. The duty ratio is adjusted so that the on-time in the on / off control of the screw member becomes longer when the screw member is larger than the target value, and when the screw member is smaller than the predetermined target value, the screw member is turned on. -The duty ratio is adjusted so that the ON time in the OFF control is reduced.

  According to a fourth aspect of the present invention, there is provided the toner replenishing device according to any one of the first to third aspects, wherein the adjustment of the drive control of the screw member is performed when the device is operated for the first time, Alternatively, and / or when the new toner container is installed.

  A toner replenishing device according to a fifth aspect of the present invention is the toner replenishing device according to any one of the first to fourth aspects, wherein the drive unit is a DC motor that also drives the toner container. Both members are rotationally driven so that the rotation cycle of the screw member and the rotation cycle of the rotary shaft on which the flexible member is installed coincide with each other.

  A toner replenishing device according to a sixth aspect of the present invention is the toner replenishing device according to any one of the first to fifth aspects, wherein the toner communicated with the toner conveying tube and the toner conveyed by the screw member. A toner dropping path for dropping the toner by its own weight toward the developing device is provided, and the toner transport pipe obliquely upwards the toner stored in the toner tank portion from the bottom of the toner tank portion toward the upper side of the developing device. It is formed so as to be conveyed linearly.

  A toner supply device according to a seventh aspect of the present invention is the toner supply device according to any one of the first to sixth aspects, wherein the toner container further contains a carrier in addition to the toner. The toner and carrier contained in the container are supplied to the developing device.

  An image forming apparatus according to an eighth aspect of the present invention includes the toner replenishing device according to any one of the first to seventh aspects, the toner container, and the developing device. It is.

  In the present invention, the drive time for one rotation of the screw member is obtained from the output fluctuation period of the detection means, and the drive control of the screw member is adjusted based on the obtained result. It is possible to provide a toner replenishing device and an image forming apparatus that are less likely to vary in the amount of toner replenished to the developing device even if the load on the portion changes.

1 is an overall configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating an image forming unit in the image forming apparatus of FIG. 1. FIG. 3 is a schematic diagram illustrating a toner container and a toner tank unit. FIG. 3 is a cross-sectional view illustrating a toner supply device. FIG. 4 is a cross-sectional view illustrating a toner transport unit in which a permanent magnet is installed. FIG. 3 is a side view illustrating an appearance of a toner supply device. FIG. 3 is a perspective view illustrating an appearance of a toner supply device. FIG. 3 is a schematic view of a toner tank portion as viewed from the side. 6 is a timing chart showing on / off control of a toner conveying screw. (A) A graph showing a change in toner replenishment amount per time when the control in the first embodiment is performed, and (B) toner replenishment amount per time when the control in the first embodiment is not performed. And a graph showing fluctuations in (A) A graph showing the toner replenishment amount for each toner container when the control in the first embodiment is performed, and (B) a toner replenishment amount for each toner container when the control in the first embodiment is not performed. And a graph.

Embodiment.
Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or it corresponds, The duplication description is simplified or abbreviate | omitted suitably.

First, the configuration and operation of the entire image forming apparatus will be described.
As shown in FIG. 1, four toner containers 32Y, 32M, 32C, and 32K corresponding to the respective colors (yellow, magenta, cyan, and black) are attached to and detached from the toner container accommodating portion 31 above the image forming apparatus main body 100. It is installed freely (changeable).
An intermediate transfer unit 15 is disposed below the toner container housing 31. Image forming portions 6Y, 6M, 6C, and 6K corresponding to the respective colors (yellow, magenta, cyan, and black) are arranged in parallel so as to face the intermediate transfer belt 8 of the intermediate transfer unit 15.
Below the toner containers 32Y, 32M, 32C, and 32K, toner replenishing devices 60Y, 60M, 60C, and 60K are disposed, respectively. The toners stored in the toner containers 32Y, 32M, 32C, and 32K are supplied (supplemented) into the developing devices of the image forming units 6Y, 6M, 6C, and 6K by the toner replenishing devices 60Y, 60M, 60C, and 60K, respectively. )

  Referring to FIG. 2, an image forming unit 6Y corresponding to yellow includes a photosensitive drum 1Y, a charging unit 4Y disposed around the photosensitive drum 1Y, a developing device 5Y (developing unit), a cleaning unit 2Y, It is comprised by the static elimination part (not shown) etc. Then, an image forming process (charging process, exposure process, developing process, transfer process, cleaning process) is performed on the photosensitive drum 1Y, and a yellow image is formed on the photosensitive drum 1Y.

  The other three image forming units 6M, 6C, and 6K have substantially the same configuration as that of the image forming unit 6Y corresponding to yellow except that the color of the toner used is different. A corresponding image is formed. Hereinafter, description of the other three image forming units 6M, 6C, and 6K will be omitted as appropriate, and only the image forming unit 6Y corresponding to yellow will be described.

Referring to FIG. 2, the photosensitive drum 1Y is driven to rotate clockwise in FIG. 2 by a drive motor (not shown). Then, the surface of the photosensitive drum 1Y is uniformly charged at the position of the charging unit 4Y (a charging process).
After that, the surface of the photosensitive drum 1Y reaches the irradiation position of the laser beam L emitted from the exposure device 7 (see FIG. 1), and the electrostatic latent image corresponding to yellow by exposure scanning at this position. Is formed (this is an exposure step).

Thereafter, the surface of the photosensitive drum 1Y reaches a position facing the developing device 5Y, and the electrostatic latent image is developed at this position to form a yellow toner image (developing process).
Thereafter, the surface of the photosensitive drum 1Y reaches a position facing the intermediate transfer belt 8 and the first transfer bias roller 9Y, and the toner image on the photosensitive drum 1Y is transferred onto the intermediate transfer belt 8 at this position. (This is a primary transfer step.) At this time, a small amount of untransferred toner remains on the photosensitive drum 1Y.

Thereafter, the surface of the photosensitive drum 1Y reaches a position facing the cleaning unit 2Y, and untransferred toner remaining on the photosensitive drum 1Y at this position is mechanically collected by the cleaning blade 2a (in the cleaning process). is there.).
Finally, the surface of the photosensitive drum 1Y reaches a position facing a neutralization unit (not shown), and the residual potential on the photosensitive drum 1Y is removed at this position.
Thus, a series of image forming processes performed on the photosensitive drum 1Y is completed.

The image forming process described above is performed in the other image forming units 6M, 6C, and 6K in the same manner as the yellow image forming unit 6Y. That is, the laser beam L based on the image information is emitted from the exposure unit 7 disposed below the image forming unit onto the photosensitive drums of the image forming units 6M, 6C, and 6K. Specifically, the exposure unit 7 emits laser light L from a light source, and irradiates the photosensitive drum through a plurality of optical elements while scanning the laser light L with a polygon mirror that is rotationally driven.
Thereafter, the toner images of the respective colors formed on the respective photosensitive drums through the developing process are transferred onto the intermediate transfer belt 8 in an overlapping manner. In this way, a color image is formed on the intermediate transfer belt 8.

  Here, referring to FIG. 1, the intermediate transfer unit 15 includes an intermediate transfer belt 8, four primary transfer bias rollers 9Y, 9M, 9C, 9K, a secondary transfer backup roller 12, a plurality of tension rollers, and an intermediate transfer. It consists of a cleaning unit, etc. The intermediate transfer belt 8 is stretched and supported by a plurality of roller members, and is endlessly moved in the direction of the arrow in FIG.

The four primary transfer bias rollers 9Y, 9M, 9C, and 9K respectively sandwich the intermediate transfer belt 8 with the photosensitive drums 1Y, 1M, 1C, and 1K to form a primary transfer nip. Then, a transfer bias reverse to the polarity of the toner is applied to the primary transfer bias rollers 9Y, 9M, 9C, and 9K.
The intermediate transfer belt 8 travels in the direction of the arrow and sequentially passes through the primary transfer nips of the primary transfer bias rollers 9Y, 9M, 9C, and 9K. In this way, the toner images of the respective colors on the photosensitive drums 1Y, 1M, 1C, and 1K are primarily transferred while being superimposed on the intermediate transfer belt 8.

  Thereafter, the intermediate transfer belt 8 on which the toner images of the respective colors are transferred in a superimposed manner reaches a position facing the secondary transfer roller 19. At this position, the secondary transfer backup roller 12 sandwiches the intermediate transfer belt 8 with the secondary transfer roller 19 to form a secondary transfer nip. The four-color toner images formed on the intermediate transfer belt 8 are transferred onto a transfer material P such as transfer paper conveyed to the position of the secondary transfer nip. At this time, the untransferred toner that has not been transferred to the transfer material P remains on the intermediate transfer belt 8.

Thereafter, the intermediate transfer belt 8 reaches the position of an intermediate transfer cleaning unit (not shown). At this position, the untransferred toner on the intermediate transfer belt 8 is collected.
Thus, a series of transfer processes performed on the intermediate transfer belt 8 is completed.

Here, the transfer material P transported to the position of the secondary transfer nip is transported from a paper feed unit 26 disposed below the apparatus main body 100 via a paper feed roller 27, a registration roller pair 28, and the like. It has been done.
Specifically, a plurality of transfer materials P such as transfer paper are stored in the paper supply unit 26 in a stacked manner. When the paper feed roller 27 is rotated in the counterclockwise direction in FIG. 1, the uppermost transfer material P is fed between the rollers of the registration roller pair 28.

  The transfer material P conveyed to the registration roller pair 28 is temporarily stopped at the position of the roller nip of the registration roller pair 28 that has stopped rotating. Then, the registration roller pair 28 is rotationally driven in synchronization with the color image on the intermediate transfer belt 8, and the transfer material P is conveyed toward the secondary transfer nip. In this way, a desired color image is transferred onto the transfer material P.

Thereafter, the transfer material P on which the color image has been transferred at the position of the secondary transfer nip is conveyed to the position of the fixing unit 20. At this position, the color image transferred to the surface is fixed on the transfer material P by heat and pressure generated by the fixing belt and the pressure roller.
Thereafter, the transfer material P is discharged out of the apparatus through the rollers of the discharge roller pair 29. The transferred P discharged from the apparatus by the discharge roller pair 29 is sequentially stacked on the stack unit 30 as an output image.
Thus, a series of image forming processes in the image forming apparatus is completed.

Next, the configuration and operation of the developing device in the image forming unit will be described in more detail with reference to FIG.
The developing device 5Y includes a developing roller 51Y facing the photosensitive drum 1Y, a doctor blade 52Y facing the developing roller 51Y, two conveying screws 55Y disposed in the developer accommodating portions 53Y and 54Y, and toner in the developer. Consists of a density detection sensor 56Y for detecting density. The developing roller 51Y includes a magnet fixed inside, a sleeve rotating around the magnet, and the like. In the developer accommodating portions 53Y and 54Y, a two-component developer G composed of a carrier and a toner is accommodated. The developer accommodating portion 54Y communicates with the toner dropping path 64Y through an opening formed thereabove.

The developing device 5Y configured as described above operates as follows.
The sleeve of the developing roller 51Y rotates in the direction of the arrow in FIG. The developer G carried on the developing roller 51Y by the magnetic field formed by the magnet moves on the developing roller 51Y as the sleeve rotates.

  Here, the developer G in the developing device 5Y is adjusted so that the ratio of toner in the developer (toner concentration) is within a predetermined range. Specifically, according to the consumption of toner in the developing device 5Y, the toner accommodated in the toner container 32Y enters the developer accommodating portion 54Y via the toner replenishing device 60Y (see FIGS. 3 and 4). To be replenished. The configuration and operation of the toner replenishing device 60Y will be described in detail later.

  Thereafter, the toner replenished in the developer accommodating portion 54Y is circulated through the two developer accommodating portions 53Y and 54Y while being mixed and stirred together with the developer G by the two conveying screws 55Y (perpendicular to the paper surface in FIG. 2). Direction movement.) The toner in the developer G is attracted to the carrier by frictional charging with the carrier, and is carried on the developing roller 51Y together with the carrier by the magnetic force formed on the developing roller 51Y.

  The developer G carried on the developing roller 51Y is conveyed in the direction of the arrow in FIG. 2 and reaches the position of the doctor blade 52Y. The developer G on the developing roller 51Y is conveyed to a position facing the photosensitive drum 1Y (development region) after the developer amount is made appropriate at this position. The toner is attracted to the latent image formed on the photosensitive drum 1Y by the electric field formed in the development area. Thereafter, the developer G remaining on the developing roller 51Y reaches above the developer containing portion 53Y as the sleeve rotates, and is detached from the developing roller 51Y at this position.

Next, the toner replenishing device 60Y that guides the toner stored in the toner container 32Y to the developing device 5Y will be described in detail with reference to FIGS.
The toner in each toner container 32Y, 32M, 32C, 32K installed in the toner container housing portion 31 of the apparatus main body 100 is a toner replenishing device provided for each toner color according to the toner consumption in each color developing device. Each developing device is appropriately replenished by 60Y, 60M, 60C, and 60K. The four toner replenishing devices 60Y, 60M, 60C, and 60K have substantially the same structure except that the colors of toner used in the image forming process are different.

Specifically, referring to FIG. 3, when the toner container 32Y is set in the toner container accommodating portion 31 of the apparatus main body 100, a sealing member including a cap, a shutter, and the like (not shown) moves in synchronization with the setting operation. Thus, the discharge port 32Ya of the toner container 32Y is opened. As a result, the toner stored in the toner container 32Y is discharged from the discharge port 32Ya and stored in the toner tank portion 61Y of the toner replenishing device 60Y.
Here, the toner container 32Y is a substantially cylindrical toner bottle, and a spiral protrusion is provided on the inner peripheral surface thereof (a spiral groove when viewed from the outer peripheral surface side). The spiral projection is for driving the toner container 32Y to rotate in the direction of the arrow in FIG. 3 by the driving unit 71 and discharging the toner from the discharge port 32Ya. In other words, the toner container 32Y is appropriately rotated by the driving unit 71, so that the toner is appropriately supplied to the toner tank unit 61Y. The toner containers 32Y, 32M, 32C, and 32K are replaced with new ones when they reach the end of their lives (when almost all the toner to be stored is consumed and emptied).

Referring to FIG. 4, the toner replenishing device 60Y includes a toner tank unit 61Y, toner conveying units 62Y and 63Y, a toner dropping path 64Y, a stirring member 65Y, a toner end sensor 66Y (piezoelectric sensor) as a detecting unit, and a magnetic field forming unit. As a permanent magnet 68Y (see also FIG. 5).
The toner tank 61Y is disposed below the discharge port 32Ya of the toner container 32Y, and stores the toner discharged from the toner container 32Y. The bottom part of the toner tank 61Y is connected to the upstream part of the toner conveying parts 62Y and 63Y.

In addition, a toner end sensor serving as a detection unit that detects that the amount of toner stored in the toner tank 61Y is less than or equal to a predetermined amount is provided on the wall surface (a position at a predetermined height from the bottom) of the toner tank 61Y. 66Y is installed. In the present embodiment, a piezoelectric sensor is used as the toner end sensor 66Y.
Referring to FIG. 3, when the control unit 70 detects that the toner stored in the toner tank unit 61Y has become a predetermined amount or less (toner end detection) by the toner end sensor 66Y, the control unit 70 Under the control, the toner container 32Y is rotationally driven by the drive unit 71 for a predetermined time to supply toner to the toner tank unit 61Y. Further, if the toner end detection by the toner end sensor 66Y is not canceled even after such control is repeated, it is assumed that there is no toner in the toner container 32Y and is displayed on the display unit (not shown) of the apparatus main body 100. A message to prompt the user to replace the toner container 32Y is displayed. In the present embodiment, a DC motor is used as the drive unit 71.

  In addition, a stirring member 65Y that prevents aggregation of the toner stored in the toner tank 61Y is installed at the center of the toner tank 61Y (in the vicinity of the toner end sensor 66Y). The agitating member 65Y includes a rotating member 65Ya and a flexible member 65Yb made of PET (polyethylene terephthalate) or the like. The agitating member 65Y agitates the toner in the toner tank portion 61Y by rotating clockwise in FIG. To do. Further, the tip of the flexible member 65Yb of the stirring member 65Y comes into contact (sliding contact) with the detection surface 66Ya (see FIG. 8) of the toner end sensor 66Y in the rotation cycle, so that the detection of the toner end sensor 66Y is performed. This prevents the detection accuracy from deteriorating due to toner adhering to the surface. That is, the flexible member 65Yb has a function of cleaning the detection surface of the toner end sensor 66Y. Further, since the stirring member 65Y rotates clockwise in FIG. 3, the flexible member 65Yb slides the detection surface of the toner end sensor 66Y disposed on the vertical wall surface of the toner tank portion 61Y from the top to the bottom. become. As a result, the staying toner near the detection surface is always periodically subjected to the action of being swept away in the direction of gravity, and the presence / absence of the toner is still detected for the existing toner. Accordingly, the detection accuracy of the toner end sensor 66Y is improved. Note that one end of the shaft portion of the stirring member 65 </ b> Y is connected to the drive unit 71 and is rotationally driven by the drive unit 71.

Referring to FIG. 4, toner transport units 62Y and 63Y transport the toner stored in toner tank unit 61Y diagonally upward (in the direction of the arrow in FIG. 4). Specifically, the toner transport units 62Y and 63Y linearly transport the toner from the bottom (lowermost point) of the toner tank unit 61Y to above the developing device 5Y (the position of the drop port 64Ya). Then, the toner transported by the toner transport sections 62Y and 63Y (the toner that has reached the position of the drop opening 64Ya) falls by its own weight on the toner drop path 64Y and enters the developing device 5Y (developer storage section 54Y). To be replenished.
The toner conveying unit includes a toner conveying screw 62Y as a screw member that is rotationally driven in a predetermined direction and conveys toner, a toner conveying tube 63Y having an inner wall close to the toner conveying screw 62Y, and the like.

  The toner conveying screw 62Y (screw member) has a screw formed in a spiral shape in a shaft portion, and is rotatably supported by the toner conveying tube 63Y via a bearing. One end of the toner conveying screw 62Y is connected to the drive unit 71 and is driven to rotate by the drive unit 71. The toner conveying screw 62Y can be formed of a metal material or a resin material.

  6 and 7, a helical gear 82 having a twist angle of 45 degrees is provided at one end of the shaft portion of the stirring member 65Y, and a helical gear 81 that meshes with the helical gear 82. The driving force is transmitted to the stirring member 65Y via (the twist angle is set to 45 degrees). Further, a bevel gear 84 is provided at one end of the toner conveying screw 62Y, and the toner conveying screw 62Y is connected via a bevel gear 83 (installed on the shaft portion of the stirring member 65Y) meshing with the bevel gear 84. The driving force is transmitted to.

  Referring to FIG. 4, the toner conveyance pipe 63Y has an upstream side communicating with the toner tank portion 61Y, and a downstream side communicating with the toner dropping path 64Y via the dropping port 64Ya. The toner transport pipe 63Y is a tubular member made of a resin material, and a toner transport screw 62Y (screw member) is rotatably supported therein via a bearing. The gap between the outer diameter portion of the toner conveying screw 62Y and the inner wall of the toner conveying tube 63Y is set to about 0.1 to 0.2 mm. Thereby, the toner transport sections 62Y and 63Y can smoothly transport the toner diagonally upward against the direction of gravity.

As described above, in the present embodiment, the toner stored in the toner tank 61Y is transported obliquely upward by the toner transport sections 62Y and 63Y, and then the toner is replenished to the developing device 5Y by its own weight drop through the toner drop path 64Y. ing. As a result, even if the rotation of the toner conveying screw 62Y is stopped when the toner supply to the developing device 5Y is finished (pause), the toner remaining in the toner conveying tube 63Y passes through the toner dropping path 64Y. The problem of falling by its own weight in the developing device 5Y is reduced. In other words, the toner transport units 62Y and 63Y that transport the toner stored in the toner tank unit 61Y obliquely upward function as a regulating unit that regulates the amount of toner that flows from the toner transport units 62Y and 63Y to the toner dropping path 64Y. become.
Specifically, the toner in the toner transport pipe 63Y remaining at a position away from the drop port 64Ya slides down or stays at the position along the inclined toner transport pipe 63Y toward the toner tank portion 61Y. Further, the toner in the toner conveyance tube 63Y remaining in a position close to the drop port 64Ya does not drop by a large amount from the drop port 64Ya even if a large impact or the like occurs, and the toner along the inclined toner conveyance tube 63Y. Either it slides down toward the tank part 61Y or stays in that position.

Therefore, even when the driving / stopping of the toner conveying screw 62Y is repeated, highly accurate toner replenishment (stable toner replenishment) to the developing device 5Y becomes possible, and the toner concentration of the developer G in the developing device 5Y (development) Variation of the toner in the agent) can be suppressed. That is, it is possible to suppress problems such as an increase in the image density of the output image, toner scattering, and a background stain image.
Further, even if the driving / stopping of the toner conveying screw 62Y is repeated, a large amount of toner remaining in the toner conveying tube 63Y is replenished into the developing device 5Y, so that the residual toner amount in the toner tank portion 61Y is reduced. Problems that fluctuate greatly are also suppressed. Therefore, erroneous detection of toner end detection by the toner end sensor 66Y is also prevented.
To repeat, even if the cover of the apparatus main body 100 is opened and closed or the toner container 32Y is attached / detached and a large vibration is applied to the toner conveying portions 62Y and 63Y due to these operations, the toner conveying portion 62Y. , 63Y is unlikely to flow out (fall) to the developing device 5Y via the toner dropping path 64Y. Further, when the new toner is initially filled with empty toner conveying portions 62Y and 63Y from the toner container 32Y, or when images having a large image area are continuously formed (during continuous paper feeding), the toner fluidity is high. Even in such a case, the toner remaining in the toner conveying portions 62Y and 63Y is unlikely to flow out (fall) toward the developing device 5Y via the toner dropping path 64Y.

  Referring to FIG. 4, in order to ensure the above-described effect, it is preferable that toner conveying portions 62Y and 63Y are formed so that inclination angle α with respect to the horizontal direction is 5 degrees or more (α ≧ 5 degrees). . However, if the inclination angle α of the toner transport units 62Y and 63Y is excessively increased, the toner transport performance by the toner transport units 62Y and 63Y is deteriorated and the height of the apparatus in the vertical direction is increased. . In the present embodiment, the inclination angle α of the toner conveying portions 62Y and 63Y is set to about 10 degrees.

  6 and 7, a shutter 86 that opens and closes in conjunction with the attaching / detaching operation of the developing device 5Y with respect to the apparatus main body 100 is installed in the toner dropping path 64Y. Specifically, when the developing device 5Y is mounted, the shutter 86 is pushed by the developing device 5Y so as to resist the urging force of the spring 87 and moves in a direction to open the toner dropping path 64Y. On the other hand, when the developing device 5Y is taken out, the shutter 86 moves in a direction to close the toner dropping path 64Y by the urging force of the spring 87. With such a configuration, even when the developing device 5Y is taken out from the apparatus main body 100, it is possible to suppress a problem that toner is scattered from the toner dropping path 64Y into the apparatus main body 100.

Here, the toner replenishing device 60Y according to the present embodiment includes a permanent magnet 68Y (magnet) as a magnetic field forming means as a restricting means for restricting the amount of toner flowing out from the toner conveying portions 62Y and 63Y to the toner dropping path 64Y. Further, a carrier C as a magnetic material is further provided.
Specifically, referring to FIGS. 4 to 7, the permanent magnet 68Y (magnetic field forming means) forms a magnetic field inside the toner transport pipe 63Y (toner transport section), and the toner transport pipe 63Y (toner transport) The carrier C as a magnetic material accommodated in advance in the transport unit) is held on the inner wall of the toner transport tube 63Y, and is covered on the outer periphery (outer wall) of the toner transport tube 63Y.

As described above, the permanent magnet 68Y is installed on the outer periphery of the toner transport pipe 63Y and the carrier C is attracted to the inner wall of the toner transport pipe 63Y, so that the toner transport is completed when the toner supply to the developing device 5Y is finished (pause). Even if the rotational driving of the screw 62Y is stopped, the toner remaining in the toner conveying tube 63Y tends to stay at the position of the carrier C, and the toner falls by its own weight into the developing device 5Y through the toner dropping path 64Y. This will further alleviate the problem. That is, the permanent magnet 68Y and the carrier C, in addition to the toner conveying portions 62Y and 63Y disposed obliquely, are transferred from the toner conveying portions 62Y and 63Y to the toner dropping path 64Y immediately after the operation of the toner replenishing device 60Y is stopped. It functions as a regulating means for regulating the amount of toner that flows out.
Specifically, the toner in the toner transport pipe 63Y remaining at a position away from the dropping port 64Ya slides down toward the toner tank 61Y along the inclined toner transport pipe 63Y or remains at the position of the carrier C. Become. Further, the toner in the toner conveyance tube 63Y remaining in a position close to the drop port 64Ya does not drop by a large amount from the drop port 64Ya even if a large impact or the like occurs, and the toner along the inclined toner conveyance tube 63Y. Either it slides down toward the tank part 61Y or stays at the position of the carrier C.

Therefore, even when the driving / stopping of the toner conveying screw 62Y is repeated, highly accurate toner replenishment (stable toner replenishment) to the developing device 5Y becomes possible, and the toner concentration of the developer G in the developing device 5Y (development) Variation of the toner in the agent) can be suppressed. That is, it is possible to suppress problems such as an increase in the image density of the output image, toner scattering, and a background stain image.
Further, even if the driving / stopping of the toner conveying screw 62Y is repeated, a large amount of toner remaining in the toner conveying tube 63Y is replenished into the developing device 5Y, so that the residual toner amount in the toner tank portion 61Y is reduced. Problems that fluctuate greatly are also suppressed. Therefore, erroneous detection of toner end detection by the toner end sensor 66Y is also prevented.
In particular, since the carrier C is used as a magnetic body held on the inner walls of the toner conveying portions 62Y and 63Y, even if the carrier C flows out from the toner conveying portion into the developing device 5Y via the toner dropping path 64Y. Since the carrier C is the same type as the carrier in the developer G in the developing device 5Y, side effects are unlikely to occur. Further, since the carrier C can be flexibly changed in posture through a narrow gap between the toner conveyance tube 63Y and the toner conveyance screw 62Y, the above-described effects can be obtained without damaging the toner conveyance tube 63Y and the toner conveyance screw 62Y. Can be achieved.
The carrier C (magnetic material) is held in advance in the toner transport units 62Y and 63Y when the image forming apparatus 100 is shipped from the factory.

In the present embodiment, since the permanent magnet 68Y is used as the magnetic field forming means, the apparatus can be reduced in space and cost compared to the case where an electromagnet or the like is used as the magnetic field forming means.
Here, it is preferable that the permanent magnet 68Y is formed so that the magnetization direction thereof is directed only to the inside of the toner conveying portions 62Y and 63Y. Specifically, as shown in FIG. 5 (a cross-sectional view taken along the line AA in FIG. 4), the S poles and the N poles are alternately arranged in a circumferential manner, and a single-sided surface is manufactured by a known manufacturing method. A pole magnetized permanent magnet 68Y is formed. As a result, defects caused by the magnetic field of the permanent magnet 68Y acting on the outside of the toner conveying portions 62Y and 63Y (for example, a change in the behavior of the developer of the developing device 5Y or a malfunction of the toner end sensor 66Y). )) Can be suppressed.

Further, referring to FIG. 4, in the toner transport pipe 63Y (toner transport section), the thickness of the portion where the permanent magnet 68Y is installed is larger than the thickness of the portion where the permanent magnet 68Y is not installed. It is formed to be thin. As a result, the magnetic force generated by the permanent magnet 68Y easily acts on the inside of the toner transport tube 63Y.
In the present embodiment, the magnetic force (magnetic flux density) of the permanent magnet 68Y is set to be 50 mT (millimeter tesla) or more. Further, the width of the permanent magnet 68Y (the length in the transport direction) is set to about 6 mm.

  Referring to FIG. 4, in the present embodiment, the right wall surface 61Ya is inclined more gently than the left wall surface 61Yb toward the toner tank portion 61Y. Immediately above the gentle inclined surface (the right wall surface 61Ya described above), a sponge seal 69Y that is compressed between the toner container 32Y and the toner tank portion 61Y and fills the gap between the both 32Y and 61Y, and its A partly formed opening (toner receiving port 69Ya) is provided. Below the gentle inclined surface 61Ya, an outer peripheral surface 61Yc of the toner conveying tube 63Y that forms a more gently inclined sliding surface is provided. The toner supplied from the toner container 32Y through the toner receiving port 69Ya is first loosened by colliding with the rotating shaft 65Ya and the flexible member 65Yb of the stirring member 65Y above the gentle inclined surface 61Ya. . Further, while loosening the sloping surfaces 61Ya and 61Yc that gradually become loose, they slip and flow into the upstream side (tilted lower end side) of the toner transport screw 62Y. With such a configuration, it is possible to set a long toner conveyance path in a relatively small space, and it is possible to improve toner agitation by providing a plurality of collision locations.

Further, as shown in FIGS. 4, 6, and 7, the permanent magnet 68Y is wound so that the upper half is bent obliquely with respect to the toner conveying tube 63Y. Accordingly, the amount of the carrier C held at a position facing the upper portion of the toner conveyance screw 62Y can be relatively increased while maintaining the above-described long toner conveyance path (the ability to regulate the amount of toner flowing out). Therefore, the toner can be prevented from jumping to the upper part of the toner conveying screw 62Y and flowing out to the toner dropping path 64Y.
Further, the permanent magnet 68Y is installed in the vicinity of the toner dropping path 64Y. As a result, the toner in the toner transport pipe 63Y remaining at a position close to the drop opening 64Ya does not fall by a large amount from the drop opening 64Ya, and easily stays at that position.

In the present embodiment, referring to FIG. 4, the toner conveyance tube 63Y has a length W (conveyance path length) from the toner tank portion 61Y to the toner dropping path 64Y, and a screw pitch D of the toner conveyance screw 62Y. (W ≧ 1.5 × D).
When the ratio (W / D) between the conveyance path length W and the screw pitch D is increased from 1, the time until the toner flows out to the toner dropping path 64Y is increased, and the ratio between the conveyance path length W and the screw pitch D is increased. When (W / D) is 1.5 or more, the time until the outflow of toner to the toner dropping path 64Y is sufficiently long and becomes a constant value. Therefore, the ratio (W / D) between the conveyance path length W and the screw pitch D is set to 1.5 or more.

Hereinafter, characteristic control performed in the toner replenishing device 60Y in the present embodiment will be described in detail.
In the present embodiment, in the toner replenishing device 60Y (image forming apparatus 100) configured as described above, the toner conveying screw 62Y (screw member) makes one rotation from the output fluctuation cycle of the toner end sensor 66Y (detecting means). The driving time is calculated, and the driving control of the toner conveying screw 62Y is adjusted based on the result (driving time for one rotation).
This is because a flexible member 65Yb that cleans the detection surface 66Ya by contacting the detection surface 66Ya of the toner end sensor 66Y that detects that the amount of toner stored in the toner tank 61Y has become a predetermined amount or less is installed. When the rotation shaft 65Ya (stirring member 65Y) is rotationally driven by the drive unit 71 that drives the toner conveyance screw 62Y, the drive time for the toner conveyance screw unit 62Y to make one rotation is the output fluctuation of the toner end sensor 66Y. This is because it is indirectly determined from the cycle.

  Specifically, immediately after the flexible member 65Yb contacts the detection surface 66Ya of the toner end sensor 66Y (piezoelectric sensor) in the rotation cycle of the stirring member 65Y (rotation shaft 65Ya), the toner attached on the detection surface 66Ya is instantaneous. As a result, the output of the toner end sensor 66Y instantaneously drops to about 0 volts, assuming that the toner is in an end state. Immediately after that, the area around the detection surface 66Ya that is instantaneously a gap is filled with the toner in the toner tank 61Y, and the output of the toner end sensor 66Y is 4 to 4 assuming that it is not in the toner end state. Return to about 5 volts. Such an output fluctuation of the toner end sensor 66Y is periodically generated in accordance with the rotation period of the stirring member 65Y (the rotation shaft 65Ya). That is, every time the flexible member 65Yb makes one rotation and contacts the detection surface 66Ya, a cycle in which the output of the toner end sensor 66Y of about 4 to 5 volts instantaneously decreases to about 0 volts is repeated. .

  The agitating member 65Y (rotating shaft 65Ya) on which the flexible member 65Yb is installed transmits (inputs) the driving force from the same driving unit 71 together with the toner conveying screw 62Y, so that the toner conveying screw unit 62Y The driving time for one rotation (or the rotation amount per unit time) is indirectly obtained from the output fluctuation period of the toner end sensor 66Y. That is, the rotation period in which the flexible member 65Yb contacts the detection surface 66Ya is obtained from the output fluctuation period of the toner end sensor 66Y, and the drive time for one rotation of the toner conveying screw 62Y is obtained from the rotation period. become.

In the present embodiment, both the members 62Y and 62Y are arranged so that the rotation cycle of the toner conveying screw 62Y and the rotation cycle of the stirring member 65Y (rotation shaft 65Ya) on which the flexible member 65Yb is installed coincide with each other. 65Y is rotationally driven by the drive unit 71.
Specifically, referring to FIGS. 6 and 7, the driving force of the drive unit 71 (DC motor) is changed from the helical gear 81 on the shaft connected to the drive unit 71 to the helical gear 82 (stirring member). Is transmitted to the agitating member 65Y via the rotating shaft 65Ya of the 65Y), and further the bevel gear 83 (installed on the rotating shaft 65Ya of the agitating member 65Y) and the bevel gear 84 (toner conveying screw). The toner is transferred to the toner conveying screw 62Y via the shaft 62Y). Here, since the gear ratio of the two bevel gears 83 and 84 is set to 1: 1, the rotation cycle of the toner conveying screw 62Y and the rotation cycle of the stirring member 65Y (rotation shaft 65Ya) coincide with each other. Will do. Therefore, the rotation cycle (driving time for one rotation) of the toner conveying screw 62Y is obtained from the output fluctuation cycle of the toner end sensor 66Y.
In the present embodiment, the rotation cycle of the toner conveying screw 62Y and the rotation cycle of the stirring member 65Y coincide with each other. However, when the rotation cycles of both the members 62Y and 65Y do not match (two bevel gears). Even when the gear ratio of 83 and 84 is set so as not to be 1: 1, the toner is detected based on the output fluctuation period of the toner end sensor 66Y based on a predetermined rotation period ratio. The rotation period (driving time for one rotation) of the transport screw 62Y can be obtained.

In the present embodiment, the driving time (rotation period) per rotation of the toner conveying screw 62Y obtained from the output fluctuation period of the toner end sensor 66Y is a predetermined target value (load fluctuation of the driving unit 71). The duty cycle is adjusted so that the on-time in the on / off control of the toner transport screw 62Y is increased. When the value is smaller than a predetermined target value, the duty ratio is adjusted so that the ON time in the ON / OFF control of the toner conveying screw 62Y is reduced.
Specifically, as shown in FIG. 9A, at the normal time, the drive unit 71 is controlled so that the duty ratio in the on / off control of the toner conveying screw 62Y (control unit 71) becomes a target value. . On the other hand, as shown in FIG. 9B, when the driving time (rotation amount per unit time) for one rotation of the toner conveying screw unit 62Y is larger than the target value (the output fluctuation of the toner end sensor 66Y). In the case where the period is long), it is assumed that the load applied to the drive unit 71 is larger than that in the normal state and the rotation period of the toner conveying screw 62Y is delayed. In order to compensate for the decrease in the toner transport amount, the duty ratio is adjusted so that the on-time in the on / off control of the toner transport screw 62Y is increased. Further, as shown in FIG. 9C, when the driving time (rotation amount per unit time) for one rotation of the toner conveying screw part 62Y is smaller than the target value (the output fluctuation period of the toner end sensor 66Y is short). In this case, it is assumed that the load applied to the driving unit 71 is smaller than that in the normal state and the rotation period of the toner conveying screw 62Y is fast, and the toner per unit time of the toner conveying screw 62Y is assumed. In order to eliminate the increase in the transport amount, the duty ratio is adjusted so that the on time in the on / off control of the toner transport screw 62Y is reduced.

Such control is performed when the load applied to the drive unit 71 that drives the toner conveying screw 62Y changes, and the driving time (the amount of rotation per unit time) for the toner conveying screw 62Y to rotate once changes. It is because it ends.
FIG. 10A shows the toner replenishing device 60Y to the developing device 5Y when the above-described on / off control of the toner conveying screw 62Y is adjusted (when the control in the present embodiment is performed). 5 is a graph showing fluctuations in the toner replenishment amount per time. FIG. 10B shows the toner supply device 60Y to the developing device 5Y when the above-described on / off control of the toner conveying screw 62Y is not adjusted (conventional control is performed). 5 is a graph showing fluctuations in the toner replenishment amount per time. From the results of FIG. 10, it can be seen that by performing the control in the present embodiment, the toner amount replenished to the developing device 5Y by the toner replenishing device 60Y (toner conveying screw 63Y) is less likely to vary.

In particular, the toner replenishing device 60Y in the present embodiment is configured to drive the toner container 32Y having a large variation in driving torque by the driving unit 71 that drives the toner conveying screw 62Y and the stirring member 65Y. Since the load fluctuation in the unit 71 becomes large, it is useful to perform the above-described control.
FIG. 11A shows four different toner containers 32Y (toner bottles) in the case where the above-described on / off control of the toner conveying screw 62Y is adjusted (the control in the present embodiment is performed). 6 is a graph showing a change in toner replenishment amount per one time from the toner replenishing device 60Y to the developing device 5Y when A to D) are used. FIG. 11B shows four different toner containers 32Y (toner bottles) when the above-described on / off control of the toner conveying screw 62Y is not adjusted (when the conventional control is performed). 6 is a graph showing a change in toner replenishment amount per one time from the toner replenishing device 60Y to the developing device 5Y when A to D) are used. From the results of FIG. 11, the amount of toner to be replenished to the developing device 5Y by the toner replenishing device 60Y (toner conveying screw 63Y) even when a different toner container 32Y is used by performing the control in the present embodiment. It can be seen that variations are less likely to occur.

  In the present embodiment, the adjustment of the drive control of the toner conveying screw 62Y described above is performed at the timing when the toner replenishing device 60Y (image forming apparatus 100) is first operated at the time of arrival or the like, and a new toner container 32Y is replaced. It is preferable to be performed at the timing when the toner is installed (the timing when the toner end recovery operation is performed). This is because, as described above, when different toner containers 32Y are used, the toner amount replenished to the developing device 5Y by the toner replenishing device 60Y (toner conveying screw 63Y) tends to vary. By adjusting the drive control of the toner conveying screw 62Y at the timing described above, the effect of the present embodiment is more reliably exhibited.

  In the present embodiment, the adjustment of the drive control of the toner conveying screw 62Y described above may be performed every time the drive unit 71 is driven for a predetermined time. As a result, even if the load applied to the drive unit 71 that drives the toner transport screw 62Y changes with time, the drive control of the toner transport screw 62Y can be appropriately adjusted according to the load fluctuation. The effect in the present embodiment will be exhibited more reliably.

  In the present embodiment, since a DC motor is used as the drive unit 71 (drive motor), when a load change occurs, a change occurs in the rotation cycle (drive time for one rotation) of the toner transport screw 62Y. Cheap. Therefore, it is useful to adjust the drive control of the toner conveying screw 62Y in the present embodiment described above.

  As described above, in the present embodiment, the driving time for one rotation of the toner conveying screw 62Y (screw member) is obtained from the output fluctuation cycle of the toner end sensor 66Y (detecting means), and based on the obtained result. In addition, since the drive control of the toner conveying screw 62Y is adjusted, even if the load applied to the driving unit 71 that drives the toner conveying screw 62Y changes, the amount of toner supplied to the developing device 5Y varies. Can be reduced.

  In this embodiment, the toner dropping path 64Y is formed in the vertical direction, and the toner is dropped in the vertical direction in the toner dropping path 64Y. However, the toner dropping path 64Y is inclined with respect to the vertical direction. The toner can be dropped by its own weight while sliding down on the inclined surface. That is, in the present application, “dropping due to the weight of the toner” is defined as including falling in the tilt direction in addition to falling in the vertical direction.

  In the present embodiment, only the toner is accommodated in the toner container 32Y, 32M, 32C, 32K, but an image forming apparatus that appropriately supplies a two-component developer composed of toner and carrier to the developing device. In contrast, the two-component developer can be accommodated in the container bodies of the toner containers 32Y, 32M, 32C, and 32K. Even in that case, the same effects as those of the present embodiment described above can be obtained.

  In the present embodiment, part or all of the image forming units 6Y, 6M, 6C, and 6K may be a process cartridge. Even in that case, the same effects as those of the present embodiment described above can be obtained.

  In the present embodiment, the driving unit 71 drives the toner container 32Y and the toner conveying screw 62Y and the stirring member 65Y. However, the driving force is supplied to the toner container 32Y. In addition, a clutch means such as an electromagnetic clutch is installed in each of the portions where the driving force is supplied to the toner conveying screw 62Y and the stirring member 65Y so that the respective driving can be turned on and off at different timings. You can also. Even in that case, the same effects as those of the present embodiment described above can be obtained.

  Further, in the present embodiment, the toner replenishing devices 60Y, 60M, 60C, and 60K are all configured with reference to FIG. 1, each of the toner tank unit (61Y), the toner transport unit (62Y, 63Y), and the toner dropping path ( 64Y) is formed in an inverted N-shape (Russian character-like shape) (N-shape when viewed from the back side of FIG. 1). The toner transport sections (62Y, 63Y) for the respective colors are provided above the process cartridges (image forming section 6Y) for the corresponding colors and above the attachment / detachment opening of the process cartridge with respect to the apparatus main body 100. Further, the upstream side in the transport direction of the toner container (32Y), the toner tank unit (61Y), and the toner transport unit (62Y, 63Y) of each color is not a process cartridge of the corresponding color but an adjacent process cartridge (left side in FIG. It is provided above. With such a configuration, in the tandem image forming apparatus in which a plurality of process cartridges (image forming units) are arranged in parallel, the process cartridge and the toner replenishing device are used when the process cartridge (image forming unit) is attached and detached. In addition, the vertical layout from the toner containers of the respective colors to the process cartridges can be made compact, and an image forming apparatus that does not cause the variation in the toner replenishment amount described above can be provided.

  It should be noted that the present invention is not limited to the present embodiment, and it is obvious that the present embodiment can be modified as appropriate within the scope of the technical idea of the present invention, other than suggested in the present embodiment. is there. In addition, the number, position, shape, and the like of the constituent members are not limited to the present embodiment, and the number, position, shape, and the like suitable for implementing the present invention can be achieved.

5Y developing device,
32Y, 32M, 32C, 32K toner containers,
60Y, 60M, 60C, 60K toner supply device,
61Y toner tank,
62Y toner conveying screw (screw member),
63Y toner transfer tube,
64Y toner drop path,
64 Ya drop port,
65Y stirring member,
65 Ya rotation axis,
65Yb flexible member,
66Y toner end sensor (detection means),
66Ya detection surface,
100 Image forming apparatus main body (apparatus main body).

JP 2010-2671 A JP 2004-139031 A

Claims (8)

A toner replenishing device for replenishing the toner contained in the toner container to the developing device,
A toner tank for storing toner discharged from the toner container;
A screw member that is close to an inner wall of a toner conveyance tube that communicates with the toner tank unit and that is rotated in a predetermined direction by a driving force input from a driving unit and conveys toner stored in the toner tank unit;
With
The toner tank portion
Detecting means for detecting that the amount of toner stored in the interior is below a predetermined amount;
A flexible member that cleans the detection surface by contacting the detection surface of the detection means while rotating together with a rotary shaft that is rotationally driven in a predetermined direction by a driving force input from the drive unit;
Comprising
A toner replenishing device, wherein a driving time for one rotation of the screw member is obtained from an output fluctuation period of the detecting means, and the driving control of the screw member is adjusted based on the driving time for one rotation.   The rotation period in which the flexible member contacts the detection surface is obtained from the output fluctuation period of the detection means, and the drive time for one rotation of the screw member is obtained from the rotation period. Item 2. The toner replenishing device according to Item 1.   When the driving time for one rotation obtained from the output fluctuation period of the detecting means is larger than a predetermined target value, the duty ratio is set so that the on time in the on / off control of the screw member is increased. The duty ratio is adjusted so that the ON time in the ON / OFF control of the screw member is reduced when the adjustment is smaller than a predetermined target value. The toner replenishing device according to claim.   The adjustment of the drive control of the screw member is performed at a timing when the apparatus is operated for the first time and / or when a new toner container is installed. A toner replenishing device according to claim 1.   The drive unit is a DC motor that also drives the toner container, and both the members are arranged so that the rotation period of the screw member and the rotation period of the rotation shaft on which the flexible member is installed coincide with each other. The toner replenishing device according to claim 1, wherein the toner replenishing device is driven to rotate. A toner dropping path that communicates with the toner conveying pipe and that causes the toner conveyed by the screw member to fall toward the developing device by its own weight;
The toner conveying pipe is formed so as to linearly convey the toner stored in the toner tank portion obliquely upward from the bottom of the toner tank portion toward the upper side of the developing device. The toner replenishing device according to claim 1. The toner container further contains a carrier in addition to the toner,
The toner replenishing device according to claim 1, wherein the toner and the carrier contained in the toner container are replenished to the developing device.   An image forming apparatus comprising: the toner supply device according to claim 1; the toner container; and the developing device.

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