JP2008249984A - Toner replenishment device and image forming apparatus equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner replenishment device capable of preventing toner from being scattered to the inside of an image forming apparatus main body, and an image forming apparatus equipped therewith. <P>SOLUTION: The toner replenishment device (20) constituted to be attached to/detached from the image forming apparatus main body (2) and replenishing a developing device (21) with toner includes: a container main body (40) having a supply toner storing part (62) storing toner to be supplied, a conveying member (70) feeding the toner in the supply toner storing part to the developing device, and a collected toner storing part (64) storing the toner remaining on an image carrier; a partition (60) formed in the container main body, partitioning the supply toner storing part and the collected toner storing part, and also capable of moving from the end wall (50) on the collected toner storing part side toward the end wall (48) on the supply toner storing part side; and partition drive mechanisms (78 and 80) moving the partition in accordance with the drive of the conveying member. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a toner replenishing device used in an image forming apparatus represented by a copying machine, a printer, a facsimile, and the like, and an image forming apparatus equipped with the toner replenishing device.

  In this type of image forming apparatus, an image is formed using toner, a toner image is formed on an image carrier, for example, a photosensitive drum, and the image is transferred and fixed on a sheet.

  Here, the consumed toner needs to be replenished separately. A cartridge-type toner replenishing device is used for this toner replenishment. The used toner replenishing device is taken out from the image forming apparatus main body by a user or the like, and a new toner replenishing device is attached to the apparatus main body. On the other hand, toner remains on the drum. For this reason, a technique is known in which the toner is collected by a cleaning device and the collected toner is collected in the above-described toner replenishing device (see, for example, Patent Documents 1 and 2).

JP-A-5-107918 JP-A-9-166912

By the way, in the conventional technology described above, the inside of the container body of the replenishing device is partitioned into a supply side and a recovery side by a partition, and the partition moves from the recovery side toward the supply side.
However, the partition moves in the container main body according to the amount of collected toner, and pressure acts on the collecting side, so that the toner on the collecting side is scattered from the container main body and the like into the apparatus main body. There is a problem that the inside of the device is contaminated.

In particular, if the partition wall is simply moved in the container body as in the above-described conventional technique, if there is toner left in the container body for a long time, the fluidity of the toner is lowered and the movement of the partition wall becomes difficult. A larger pressure acts on the recovery side than on the supply side.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a toner replenishing device that can solve the above-described problems and prevent toner from scattering into the apparatus main body, and an image forming apparatus equipped with the toner replenishing device.

  A first invention for achieving the above object is a toner replenishing device configured to be detachable from an image forming apparatus main body and replenishing toner to a developing device, and a supply toner accommodating portion for accommodating toner to be replenished, A container main body having a transport member for sending the toner in the supply toner storage portion toward the developing device, a recovery toner storage portion for recovering the toner remaining on the image carrier, and a supply toner formed in the container main body. The storage unit and the collected toner storage unit are partitioned, a partition wall that is movable from an end wall on the recovery toner storage unit side toward an end wall on the supply toner storage unit side, and the partition wall is moved according to driving of the conveying member And a partition wall driving mechanism.

According to the first aspect of the present invention, the toner replenishing device is provided with a container main body having a supply toner accommodating portion that accommodates toner to be replenished and a collected toner accommodating portion that collects toner remaining on the image carrier. These two storage parts are partitioned through a partition wall.
The toner replenishing device has a partition drive mechanism, and moves the partition from the end wall on the collected toner storage unit side toward the end wall on the supply toner storage unit side according to the driving of the conveying member. Therefore, a large pressure does not act on the collected toner storage portion as in the prior art. As a result, it is possible to prevent toner from scattering into the apparatus main body.
In addition, since the partition is actively moved in the container main body according to the driving of the conveying member, even if the fluidity of the toner is lowered, the partition can be easily moved as compared with the conventional case. .

According to a second aspect of the invention, in the configuration of the first aspect, the partition wall driving mechanism moves the partition wall by the amount of toner reduced in the supply toner storage portion by supply to the developing device.
According to the second invention, in addition to the action of the first invention, the partition wall moving mechanism moves the partition wall by an amount sent from the replenishing device by supplying toner to the developing device. Therefore, when the toner is collected, the volume of the collected toner storage unit is increased in advance, and preparations for receiving the collected toner are already made, so that no great pressure is applied to the collected toner storage unit.

According to a third invention, in the configuration of the first or second invention, the partition wall is closest to the end wall on the supply toner storage portion side when the volume in the supply toner storage portion becomes substantially zero. And
According to the third aspect of the invention, in addition to the operation of the first aspect, the movement of the partition wall ends with the end of the time required for toner replenishment. The amount of increase in the volume of the toner becomes equal, and the scattering of the toner into the apparatus main body can be prevented more reliably.

The fourth invention is characterized in that the first to third toner replenishing devices are mounted on the image forming apparatus and toner is replenished to the developing device using the same.
According to the fourth invention, in addition to the action of the first invention, toner scattering into the apparatus main body is prevented, and as a result, a good image can be obtained, which contributes to improving the reliability of the image forming apparatus.

  According to the present invention, it is possible to provide a toner replenishing device in which the partition wall positively moves in the container main body and prevents the toner from scattering into the apparatus main body, and an image forming apparatus equipped with the toner replenishing device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 schematically shows the structure of a printer 1 which is an example of an image forming apparatus. The cross section shown in the figure is seen from the left side of the printer 1. For this reason, the front surface of the printer 1 is positioned on the right side and the rear surface of the printer 1 is positioned on the left side.

  As shown in the figure, a paper storage device 4 is disposed below the inside of the device main body 2 of the printer 1. The storage device 4 is equipped with a base cassette 6, in which the sheets P are stored in a stacked state. Then, the sheet P is sent toward the upper right side of the cassette 6 in the figure, and the sent sheet P is reversed toward the back side inside the apparatus main body 2 and conveyed toward the back side as it is. The

Further, the cassette 6 is configured to be drawn rightward in the drawing, and in this pulled out state, a new sheet P is replenished in the cassette 6 or the sheet P is loaded with another kind. It can be replaced with paper.
Inside the apparatus main body 2, a feed roller 10, a paper feed path 12 for feeding paper, a registration roller 14, an image forming unit 16, and a transfer unit 90 are sequentially arranged downstream in the paper transport direction from the paper storage device 4. Has been placed.

  The image forming unit 16 is provided with a photosensitive drum (image carrier) 18 at the center thereof. Further, an optical unit 15 is provided above the image forming unit 16, and laser light L is emitted from the optical unit 15 toward the drum 18 as indicated by a one-dot chain line in the drawing. Is done. Further, the transfer unit 90 is provided with a transfer roller 91, and this roller 91 is pressed against the drum 18 from below to form a transfer nip for transferring the toner image onto the paper P.

  Further, a fixing unit 92, a discharge paper transport path 94, and a paper discharge unit 96 are sequentially arranged on the downstream side of the image forming unit 16 and the transfer unit 90 in the paper transport direction. The sheet conveying path 94 extends upward from the downstream of the fixing unit 92 along the back surface of the apparatus main body 2, and is further bent toward the front side at the upper position of the apparatus main body 2. The paper discharge unit 96 is formed on the upper surface of the apparatus main body 2, and can receive the paper P discharged from the terminal end of the paper transport path 94 at this position and stack it in the height direction. The printed paper P stored in the paper discharge unit 96 can be easily taken out from the outside.

  On the other hand, a paper conveyance path 98 for double-sided printing is formed below the transfer unit 90 and the fixing unit 92 and between the paper storage device 4. The sheet conveyance path 98 branches from the middle of the sheet conveyance path 94 at a position along the back surface of the apparatus main body 2 and extends downward. The paper transport path 98 is bent toward the front side in the apparatus main body 2 and extends in the horizontal direction, and is joined to the paper transport path 12 at a position immediately downstream of the paper feed unit 8.

  Here, the toner replenishing device 20 is mounted on the printer 1 of the present embodiment. The replenishing device 20 is located in front of the optical unit 15 and above the paper conveyance path 12 and is configured to be detachable from the apparatus main body 2. The toner in the replenishing device 20 is supplied to the image forming unit 16 through a developing device (developing device) 21.

  More specifically, the toner replenishing device 20 of this embodiment includes a vertically long container body 40 and a lid member 42 that covers the container body 40 from above, as can be understood from FIG. 2 and FIG. ing. The container body 40 has a vertically long bottom wall 44. Side walls 46 and 47 are disposed on both side portions of the bottom wall 44, and end walls 48 and 50 are directed upward at both longitudinal end portions of the bottom wall 44, respectively. Is formed.

  A supply screw member (conveying member) 70 is disposed in the container body 40. The member 70 includes a shaft portion rotatably supported by the end walls 48 and 50, a spiral blade portion formed around the shaft portion, and a connecting portion 72 formed at the rear end of the shaft portion. The connecting portion 72 is connected to a drive motor (not shown) installed in the apparatus main body 2. In addition, although the member 70 of a present Example is comprised by the perfect screw shape, the said helical blade | wing part may be formed partially.

  On the other hand, a partition wall 60 is installed inside the container body 40. The partition wall 60 according to the present embodiment is arranged along the end walls 48 and 50, and the inside of the container body 40 is divided into two spaces by the partition wall 60. Specifically, as shown in FIG. 3, a supply toner storage portion 62 is formed between the end wall 48 and the partition wall 60, and a collected toner storage portion 64 is formed between the partition wall 60 and the end wall 50. .

  The former supply toner storage portion 62 stores toner to be supplied to the developing device 21. When a decrease in the toner amount in the developing device 21 is detected, the replenishing screw member 70 is rotated via the drive motor, and the toner around the member 70 is near the end wall 48 and on the bottom wall. The toner moves toward a toner discharge opening 52 formed at an appropriate position 44. As a result, the toner in the supply toner storage section 62 is sent to the developing device 21 through the discharge opening 52, and a toner image is formed on the drum 16 through the developing device 21 (FIG. 2).

  On the other hand, toner collected from the drum 18 is accommodated in the latter collected toner accommodating portion 64. Specifically, as shown in FIG. 2, a cleaning device 19 is disposed at an appropriate position of the drum 18. In this device 19, toner remaining on the drum 18 after being transferred onto the paper P is collected. The toner is collected in the replenishing device 20 via the toner conveying device 30.

  Specifically, the transport device 30 of the present embodiment has a tubular passage 32, one end of the passage 32 communicating with the cleaning device 19, and the other end of the passage 32 communicating with the replenishing device 20. A screw 34 is installed inside the passage 32. Then, when the screw 34 is rotated via a drive motor (not shown), the toner collected by the device 19 passes through the passage 32 and is in the vicinity of the end wall 50 located on the opposite side of the end wall 48 and on the lid member 42. It moves toward the collection opening 43 formed at an appropriate position. As a result, the toner remaining on the drum 18 is collected in the collected toner storage portion 74.

By the way, the partition wall 60 of the present embodiment is configured to be movable from the end wall 50 toward the end wall 48, and is configured to be movable in accordance with the driving of the replenishing screw member 70.
Specifically, as shown in FIG. 3, a partition wall drive mechanism is provided at an appropriate position above the replenishing screw member 70 in the container body 40.

  This mechanism has a moving screw member 78, and this member 78 is composed of a shaft portion rotatably supported by the end walls 48 and 50, and a spiral portion formed around the shaft portion. The rear end of the shaft portion is connected to a plurality of large diameter gears 76 and a plurality of small diameter gears 74 meshing with the gears 76 outside the container main body 40. Each of these gears 74 and 76 has a double gear structure. The gear 74 is rotatably supported by the end wall 50, and one of the gears 76 is meshed with the rear end of the replenishment screw member 70 described above.

On the other hand, the moving screw member 78 meshes with the support portion 80 inside the container body 40, and the support portion 80 moves from the end wall 50 toward the end wall 48 as the member 78 rotates. The support 80 is formed integrally with the partition wall 60.
Thus, the driving force for rotating the replenishing screw member 70 to replenish the toner in the supply toner storage portion 62 to the developing device 21 is via a double gear structure that obtains a large reduction ratio by the large diameter gear 76 and the small diameter gear 74. This is also transmitted to the moving screw member 78 to move the partition wall 60 from the end wall 50 toward the end wall 48.

Here, the moving screw member 78 that is driven and branched downstream of the connecting portion 72 has a predetermined reduction ratio, and the amount of toner reduced in the supplied toner storage portion 62 due to the toner supply to the developing device 21. Only the partition wall 60 is moved.
Specifically, if the maximum capacity of the supply toner storage unit 62 is 2000 g and the toner supply amount to the developing device 21 is 50 g per minute, it takes 40 minutes to supply all the toner. Become.

  Therefore, the pitch of the members 78 is set so that the partition wall 60 can move from the end wall 50 to the end wall 48 in 40 minutes. In other words, if the rotation speed of the replenishing screw member 70 is 70 rotations per minute, 2800 rotations are possible in 40 minutes, so the rotation speed of the moving screw member 78 and the rotation speed of the replenishment screw member 70 are The ratio is 40 rotations / 2800 rotations, and the reduction ratio is 1/70.

Therefore, if the moving speed of the partition wall 60 is the reduction ratio, the partition wall 60 moves by the reduced toner amount in the supply toner storage portion 62, and does not push out the toner in the storage portion 62 and collects the collected toner. The toner in the storage section 64 is not pulled in. Then, when the volume in the supply toner storage portion 62 becomes substantially zero, the end wall 48 is closest.
In this embodiment, when the replenishing device 20 is mounted on the device main body 2, the upper end of the partition wall 60 does not block the collection opening 43, and the one end side of the support portion 80 comes into contact with the inner surface of the end wall 50. On the other hand, when all the toner in the supply toner storage portion 62 is supplied to the developing device 21, the lower end of the partition wall 60 does not block the discharge opening 52, and the other end side of the support portion 80 is the inner surface of the end wall 48. Will abut.

  In the printer 1 supplied with toner by the toner replenishing device 20, the paper P before printing is stored in a state of being stacked on the base cassette 6. When the printer 1 performs printing, the paper P is supplied from the cassette 6. The paper P is separated and sent one by one by the paper unit 8. The sent paper P reaches the registration roller 14 through the paper transport path 12. The roller 14 feeds the paper P to the transfer unit 90 while correcting the oblique feeding of the paper P and timing the toner image formed by the image forming unit 16.

  Image data is transmitted to the printer 1 from an external computer (not shown). This image data is data in which various images such as characters, signs, figures, symbols, diagrams, and patterns are converted into data. Based on this data, the printer 1 controls the irradiation of the laser beam L by the optical unit 15. Is done. As a result, an electrostatic latent image of the original image is formed on the photosensitive drum 18 in the image forming unit 16, and then a toner image is formed on the drum 18 from the electrostatic latent image. This toner image is transferred onto the paper P at the transfer nip between the drum 18 and the roller 91.

Thereafter, the sheet P is fed toward the fixing unit 92 with an unfixed toner image carried thereon, and the toner image is fixed by the heat roller at the fixing unit 92. Next, the paper P discharged from the fixing unit 92 is sent upward through the paper conveyance path 94 and discharged to the paper discharge unit 96.
In contrast to this single-sided printing, when the printer 1 performs double-sided printing, the transport direction of the paper P discharged from the fixing unit 92 is switched immediately before being discharged to the paper discharge unit 96.

That is, the paper P printed on one side is pulled back into the paper transport path 94 and transported into the paper transport path 98. Subsequently, the sheet P merges with the sheet conveyance path 12 immediately downstream of the sheet feeding unit 8 and is sent toward the transfer unit 90 again. At this time, since the printed surface of the paper P is facing downward, when the paper P is sent again to the transfer unit 90, the toner image is transferred to the surface of the paper P that has not yet been printed. .
Subsequently, the toner remaining on the drum 18 is collected by the cleaning device 19, and then the toner in the passage 32 is collected by the replenishing device 20 by the rotation of the screw 34.

  As described above, according to the present exemplary embodiment, the toner replenishing device 20 includes a supply toner storage unit 62 that stores toner to be replenished and a container main body that has a collected toner storage unit 64 that collects toner remaining on the drum 18. 40, and both the storage portions 62 and 64 are partitioned by a partition wall 60. This eliminates the need for a waste toner bottle and makes it unnecessary to replace the bottle.

The replenishing device 20 has a partition wall driving mechanism, and moves the partition wall 60 from the end wall 50 toward the end wall 48 according to the driving of the replenishing screw member 70. Therefore, unlike the conventional case, a large pressure does not act on the collected toner storage portion 64 as compared with the supply toner storage portion 62. As a result, it is possible to prevent toner from scattering into the apparatus main body 2.
In addition, since the partition wall 60 is actively moved in the container main body 40 according to the driving of the replenishing screw member 70, the partition wall 60 is easier than the conventional case even if the toner fluidity is lowered. Can be moved to.

Further, the partition wall 60 is meshed with the moving screw member 78 and can be reliably moved at a desired reduction ratio.
Further, the partition moving mechanism moves the partition 60 by the amount sent from the replenishing device 20 by supplying toner to the developing device 21. Therefore, the partition wall 60 is moved when the toner is supplied, and the volume of the supply toner storage portion 62 is reduced. That is, when the toner is collected, the volume of the collected toner storage unit 64 is increased in advance, and preparations for receiving the collected toner are already made. Therefore, a large pressure does not act on the collected toner storage unit 64. The scattering of the toner into the apparatus main body 2 is reliably prevented.

Further, since the movement of the partition wall 60 ends with the end of the time required for toner replenishment, the amount of decrease in the volume of the supplied toner storage portion 62 and the amount of increase in the volume of the recovered toner storage portion 64 become equal, and the inside of the apparatus main body 2 The toner is more reliably prevented from scattering.
Furthermore, if the above-described replenishing device 20 is installed, a good image can be obtained, which contributes to improving the reliability of the printer 1.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the claims.
For example, in the above embodiment, the moving screw member 78 rotates integrally with the drive motor that drives the replenishment screw member 70, but the present invention is not necessarily limited to this configuration, and is separate from the drive motor. It may be rotated by a drive motor. Also in this case, there is an effect that the toner can be prevented from scattering into the apparatus main body 2.

  Furthermore, although the above embodiment shows an example in which the image forming apparatus is embodied in a printer, the image forming apparatus of the present invention can naturally be applied to a copying machine, a facsimile, and the like.

1 is a schematic configuration diagram of a printer according to an embodiment. FIG. 2 is a front view of the toner supply device of FIG. It is arrow sectional drawing in the III-III line of FIG.

Explanation of symbols

1 Printer (image forming device)
2 Device body (image forming device body)
18 Photosensitive drum (image carrier)
20 toner replenishing device 21 developing device (developing device)
40 Container body 48 End wall 50 End wall 60 Bulkhead 62 Supply toner storage 64 Recovery toner storage 70 Supply screw member (conveyance member)
74 Small-diameter gear (partition wall drive mechanism)
76 Large diameter gear (partition wall drive mechanism)
78 Screw member for movement (partition wall drive mechanism)
80 Supporting part (partition wall drive mechanism)

Claims (4)

A toner replenishing device configured to be detachable from the image forming apparatus main body and replenishing toner to the developing device,
A container having a supply toner storage portion for storing toner to be replenished, a conveying member for sending the toner in the supply toner storage portion toward the developing device, and a recovery toner storage portion for recovering the toner remaining on the image carrier The body,
Formed in the container main body, partitions the supply toner storage portion and the collected toner storage portion, and moves from an end wall on the recovery toner storage portion side toward an end wall on the supply toner storage portion side Possible partition walls,
A toner replenishing device, comprising: a partition wall drive mechanism that moves the partition wall according to driving of the conveying member. The toner replenishing device according to claim 1,
The toner supply device, wherein the partition drive mechanism moves the partition by an amount of toner reduced in the supply toner storage portion by supplying to the developing device. The toner replenishing device according to claim 1 or 2,
The toner replenishing device, wherein the partition wall is closest to an end wall on the supply toner storage portion side when a volume in the supply toner storage portion becomes substantially zero.   An image forming apparatus comprising: the toner replenishing device according to claim 1; and a toner replenishing unit using the toner replenishing device.

Images