JP3339272B2 - Developing device for image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in an image forming apparatus utilizing an electrophotographic system, in which a plurality of developing devices are arranged around a rotation axis, and toner is supplied from each developing device to a developing object. Related to the device.

[0002]

2. Description of the Related Art For example, in a color copying machine, a toner image is formed one layer at a time on the surface of an image carrier such as a photosensitive drum.
By laminating these, a color image is obtained by coloring. As a developing device used for this, for example, as disclosed in Japanese Patent Application Laid-Open No. 61-95370, there is a developing device in which a plurality of developing devices are arranged around a rotating shaft. In this case, each time the photosensitive drum makes one rotation, one color of toner is supplied from any of the developing devices, and when the developing is not performed,
By rotating the rotating shaft, another developing unit faces the photosensitive drum, and these operations are repeated, so that a toner image is stacked on the photosensitive drum.

The developing device used here is supplied with toner from a supply port of a detachable cylindrical toner supply container. A seal for closing the supply port is attached to the toner supply container, and a user inserts the toner supply container into a holding hole provided in the developing device while peeling off the seal. .

[0004]

However, in this case, if the seal is peeled off too quickly rather than inserting the toner supply container, the supply port is largely exposed, and the toner leaks out from the opening, and the image forming operation is performed. The device and user's clothes and hands could be stained. Also, when removing the used toner replenishing container from the holding hole, there is nothing to block the replenishing port, so that the toner inside the toner replenishing container may leak out to cause the same problem. was there.

Therefore, it is essential that the toner supply container is attached to and detached from the holding hole so that the supply port always faces upward. However, since movement such as vibration always occurs, toner leakage is completely prevented. It is difficult. Further, since a plurality of developing devices are arranged around the rotation shaft, and a plurality of toner supply containers are provided corresponding to the developing devices, the developing device is required to face the supply port of each toner supply container upward. Must be rotated, for example, by 90 °, which is bothersome and time-consuming. Also, when mounting the toner supply container, the user has to use both hands because the user must push the supply container into the holding hole with the other hand while peeling off the seal with one hand.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has a rotary developing device capable of reducing toner leakage and allowing a plurality of toner supply containers to be easily attached and detached without taking time. The purpose is to provide.

[0007]

In order to solve the above-mentioned problems, a developing device for an image forming apparatus according to the present invention comprises a rotating shaft.
Are arranged around this rotation axis,
A plurality of developing devices having an inlet and a supply outlet;
Are arranged adjacent to the developing devices, respectively.
A toner supply container having a supply port that can communicate with the inlet;
The toner supply container is attached to and detached from the rotation shaft.
Developing device for an image forming apparatus, comprising:
In the toner supply container, the supply port is opened.
A shutter is provided to close the toner supply container.
With the operation of holding the shutter, the shutter
Is opened and the supply port communicates with the intake of the developing device.
In addition, in the toner supply container,
A conveying means constituted by a first spiral is provided.
The first spiral body is rotationally driven during development.
And the toner is driven by the first helical body that is rotationally driven.
Conveys the toner in the supply container toward the intake of the developing unit
While the plurality of developing devices revolve around the rotation axis.
The first spiral body is not driven to rotate,
The toner replenishing container is revolved with the developing device so
To move the toner inside the cartridge toward the supply port.
The toner supply container and the developing port.
Between the inlet of the vessel and the second spiral
The toner flow preventing means is provided,
The prevention means is that the second spiral body is driven to rotate during the development.
And the rotation of the second spiral body causes the intake
Conveying the toner toward the
While the developing device is revolving, the second spiral body is rotated.
By revolving with the developer without being moved
This gives the toner a conveying force in the opposite direction to that during development.
You. In this case, the shutter is opened with the operation of holding the toner supply container in the holding unit, and the supply port is closed by the shutter before that, so that the supply port of the toner supply container is not exposed. It is possible.
In addition, by closing the shutter when removing the toner supply container from the holding unit after use, the supply container can be removed without exposing the supply port.
In this way, it is possible to reduce the leakage of toner when the toner supply container is attached and detached, and it is also possible to reduce the risk of soiling the clothes and hands of the image forming apparatus and the user. In addition, since the opening and closing operation of the shutter is performed in accordance with the operation of attaching and detaching the toner supply container, the user separately performs the operation of attaching and detaching the toner supply container.
There is no need to open and close the shutter, and work can be easily performed with one hand. Further, before the toner replenishing container is held by the holding portion, the replenishing port of the toner replenishing container is closed by the shutter, so that it is not always necessary to rotate the developing device so that the replenishing port faces upward. Thus, the plurality of toner replenishing devices can be attached and detached very easily in a short time. It is preferable that the holding section is provided with another shutter for closing the inlet of the developing device, and this shutter is also operated in accordance with the operation of the shutter. According to this, until the operation of holding the toner supply container in the holding unit is completed, the shutter closes the inlet of the developing device, regardless of the position of the developing device, so that leakage of toner from the developing device is prevented. Is prevented. When toner is supplied from the supply port to the intake port, a toner flow preventing means provided between the supply port of the toner supply container and the intake port of the developing device moves the toner to the supply port side. Therefore, when the toner is supplied to the image carrier by the developing device, the supply amount of the toner can be made appropriate, and the image density can be appropriately controlled.

In the above arrangement, a supply means for supplying the toner in the developing device to a developing object is provided at the supply outlet of the developing device, and the toner replenishing container is provided with the toner replenishing container. Conveying means for conveying the toner toward the inlet of the developing device may be provided, and the conveying means may be driven in conjunction with the supplying means of the corresponding developing device. According to this, when the supply unit of the developing device is driven to supply the toner to the development target, the transport unit is always driven, and the toner is transported from the transport unit to the supply unit. Therefore, it is possible to avoid insufficient density of the formed image. When the developing device rotates about the rotation axis, the toner in the toner supply container tends to disperse from the vicinity of the supply port. In particular, when the toner in the toner supply container becomes small, the toner is conveyed. The amount may be insufficient. However, by linking the transporting means with the supplying means, the time required for transporting the toner by the transporting means is increased, so that the amount of toner transported from the transporting means to the supplying means is prevented from being insufficient, and an image to be formed is formed. Occurrence of insufficient concentration can be delayed. Further, since the toner in the toner replenishing device is transported by the transporting means, the toner in the replenishing device can be used up without remaining. Therefore, if the toner supply container is disposable, the amount of wasted toner is extremely small.
The remaining toner is prevented from sticking in the toner supply container.

Here, a supply port of the toner supply container,
When the developing device rotates around the rotation axis between the inlet of the developing device and the developing device, a toner flow preventing unit that gives the toner a conveying force in a direction opposite to the movement of the developing toner is provided. Even better. In the case of a rotary developing device such as the present invention, when a transport unit that transports toner from the toner supply container to the developing device is provided, the transport unit is rotated by the rotation of the developing device, that is, the revolution of each developing device. Even when the toner is not driven, the toner may move along the contour of the conveying unit. Due to this, when then supplying toner to the image carrier by the corresponding developing unit, I supply toner Do excessive, the image may not become a concentration to be controlled. However, such a problem can be prevented by providing the toner flow prevention unit.

Further, it is preferable that when the developing device rotates about the rotation axis, the toner in the toner supply container is moved toward the supply port by the transport means. As described above, when the developing device rotates about the rotation axis, the toner in the toner supply container tends to disperse from the vicinity of the supply port, and especially when the toner in the toner supply container becomes small, If left unattended, there is a concern that the amount of toner transported from the transporting unit to the supply unit may be insufficient, but if the toner in the toner supply container is moved toward the replenishing port by the transporting unit, the toner Can be prevented from becoming insufficient, and the occurrence of insufficient density of an image to be formed can be delayed.

The developing device is disposed in an image forming apparatus having an openable / closable cover, and when the toner supply container is held by the holding portion, the toner supply container is moved within the holding portion. Thereby, the shutter is opened, and on the cover side of each of the toner supply containers, an operation unit for moving the toner supply container in the holding unit is provided so as to protrude therefrom.
When at least one of the shutters is incompletely opened, the operation unit corresponding to the shutter may inhibit the operation of closing the cover. In this case, if any one of the shutters is not sufficiently opened, the operation unit collides with the cover of the image forming apparatus,
I can't close that cover. This state is known, for example, by the user directly or by stopping the operation of the image forming apparatus by electrical means.
It is possible to check whether the shutters of all the toner supply containers are sufficiently opened. Then, the user is prevented from operating the image forming apparatus in a state where the shutter is not completely opened.

Further, a first engagement portion is provided on each of the holding portions, and a second engagement portion is provided on each of the toner supply containers, and the corresponding first engagement portion and the second engagement portion are provided. 2
It is preferable that only the engaging portion is engaged. Generally, a rotary developing device supplies a different toner to each developing device in order to form a color image. Which toner is supplied by which developing device, that is, which toner supply container is inserted in each holding unit, is predetermined in view of the control of image formation. As described above, if only the corresponding first engagement portion and second engagement portion are engaged, it is difficult or impossible to completely hold the wrong toner supply container in the holding portion. Becomes impossible. Therefore, the user becomes aware of an error in selecting the holding section into which the toner supply container is to be inserted.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. A. Configuration of Embodiment A-1. First Embodiment FIG. 1 is a front view showing a developing device 1 of an image forming apparatus according to an embodiment of the present invention. The developing device 1 has a substantially cylindrical shape, and has a rotating shaft 2 at the center thereof.

FIG. 2 is a sectional view of the developing device 1.
As shown in FIG.
The center support portion 3 supports pins 5 of four developing devices 4 at angular intervals of 90 °. Each developing device 4 includes a housing 6, a pin 5 protruding from an outer surface of the housing 6, two agitating screws 7, 8 disposed inside the housing 6, and a developing roll 9 (supply means).

In this image forming apparatus, a two-component developer comprising a toner containing a dye or a pigment based on a polyester resin and a carrier made of a magnetic powder is used. A carrier is accommodated in the housing 6, and toner is supplied from a toner supply container 10 described later. The stirring screws 7 and 8
When the developer is closest to the photosensitive drum 12, the photosensitive drum 12 is rotated in a direction indicated by an arrow in the figure to agitate the developer in the housing 6.

In the figure, reference numeral 15 denotes a partition wall provided inside the housing 6. The partition 15 divides the internal space of the housing 6 into a first developer chamber 16 provided with the stirring screw 7 and a second developer chamber 17 provided with the stirring screw 8. The stirring screws 7 and 8 are rotated in the direction of the arrow in the drawing, and the stirring screw 7 conveys the developer toward the back side of the drawing, and the stirring screw 8 conveys the developer toward the near side of the drawing. Openings (not shown) are formed at both ends of the partition wall 15, the developer conveyed to the stirring screw 7 moves to the second developer chamber 17, and the developer conveyed to the stirring screw 8 is used for the first development. It is adapted to move to the medicine chamber 16. In this way, the toner and the carrier in the developer are mixed and the toner is charged.

FIG. 3 is a developed view showing a rotating member in one developing unit 4. 2, the upper side is the back side of the paper of FIG. 2, the lower side is the front side of the paper of FIG. 2, the solid arc arrows indicate the rotation direction of the member, and the broken arrows indicate the movement direction of the developer. FIG. 3 also shows the state of movement of the developer in the housing 6 as described above. In addition, FIG.
Looking at the line III-III.

Referring back to FIG. 2, the developing roll 9 is disposed at a supply outlet 11 formed in the housing 6, and is rotated in a direction indicated by an arrow in the drawing when located at a position adjacent to the photosensitive drum 12. Supplies the toner in the housing 6 to the photosensitive drum 12. The developing roll 9 has, for example, a structure in which a sleeve is rotatably provided around a magnet roll. The developer in which the carrier and the toner are mixed is attracted to the surface by a magnet having a polarity different from that of the carrier.
The sheet is transported to the photosensitive drum 12 (development target).

The photosensitive drum 12 is supported adjacent to the developing device 1, and is rotatable in a direction indicated by an arrow A in the figure. A charger and an exposure device (not shown) are arranged around the photoconductor drum 12, and the surface of the photoconductor drum 12 is uniformly charged by the charger with the rotation of the photoconductor drum 12. The charged surface is exposed by the exposure device. In this way, a latent image corresponding to the image to be formed is formed on the surface of the photosensitive drum 12 by the photoelectric effect. Then, the developer adhered to the developing roll 9 as described above is transferred to the photosensitive drum 12.
Is reached, the charged toner in the developer is electrostatically attracted to and adheres to the latent image on the photosensitive drum 12.
On the other hand, the carrier is conveyed while being attached to the developing roll 9, and then separates from the developing roll 9 in the housing 6 by the repulsive force of a magnet having the same polarity as the carrier in the developing roll 9.

In this embodiment, when the rotating shaft 2 is driven, the developing device 1 is rotated in the direction shown by the arrow B. Then, the developing roll 9 of one of the developing devices 4 is made to be adjacent to the photosensitive drum 12, and at this time, the toner is adhered from the developing roll 9 to the photosensitive drum 12. The developing device 4
Each of black, yellow, magenta, and cyan toners is supplied to the photosensitive drum 12, and one or two rotations of the photosensitive drum 12 cause one color of the toner to be supplied onto the photosensitive drum 12. Attached to form an image. Then, after the toner image is formed,
The developing device 1 is rotated, and the developing roll 9 of the other developing device 4 is made adjacent to the photosensitive drum 12.

The toner image formed on the photosensitive drum 12 reaches a transfer corotron (not shown) with the rotation of the photosensitive drum 12, and forms an image of a sheet of paper or the like by an electric field generated by the transfer corotron. Transcribed to the subject. The image forming target is wound around a rotating transfer drum and rotated, and the toner image is repeatedly formed on the image forming target for each color, so that black,
Yellow, magenta, and cyan toners are stacked on an image forming target, and a color toner image is formed. afterwards,
The image forming object is peeled off from the transfer drum, transported to the heat fixing device, and receives heat and pressure in the heat fixing device, so that the toner is fixed on the image forming object.

As shown in FIG. 1, four substantially fan-shaped holding members (holding portions) 23 having a central angle of 90 ° are attached to the front surface (front side in the drawing) of the center supporting portion 3 of the developing device 1. I have. A substantially circular holding hole 14 is formed in each holding member 23, so that 9
There is an angular spacing of 0 °. A part of each holding hole 14 is cut out outside the developing device 1, thereby forming an opening 24.

A substantially cylindrical toner supply container 10 is inserted into each holding hole 14 and held detachably. Although not shown, a member for supporting the toner supply container 10 is provided on the back surface of the developing device 1. The toner supply container 10 contains black, yellow, magenta, and cyan toners, respectively, and a supply port 18 for discharging toner to the outside is formed in the toner supply container 10. In the toner supply container 10, only the supply port 18 is opened, and the other portions are sealed so that toner does not leak.

As shown in FIG. 2, between the toner supply container 10 and the developing device 4, a toner receiving portion 1 which is a cylindrical wall is provided.
9 are provided. The toner receiving portion 19 is formed integrally with the holding member 23. The toner receiving section 19
The toner chamber 20 is provided therein.
Communicates with a supply port 18 of the toner supply container 10, to which toner is supplied from the toner supply container 10. Further, as shown in FIG. 3, a supply port 21 is formed in the toner receiving portion 19, from which the toner falls and the developing device 4
Is supplied to the housing 6. That is, the supply port 21 is an inlet for the toner of the developing device 4,
The toner supply container 10 and the developing device 4 are in communication.

As shown in FIG. 2, a thin plate-shaped cover 22 is suspended in the housing 6 near the supply port 21 so as to be rotatable. The cover 22 opens the supply port 21 when the corresponding toner supply container 10 is on the left side in the figure, but closes the supply port 21 when the corresponding toner supply container 10 is on the right side in the figure. Developing device 4
To prevent the toner from flowing back into the toner receiving portion 19 and the carrier from flowing into the toner receiving portion 19.

As shown in FIGS. 1 and 3, the developing device 4 is provided on the back side of the holding member 23, but the toner replenishing container 10 is not only on the back side of the holding member 23 but also on the front side. It is held at a position slightly protruding to the side. The replenishing port 18 of the toner replenishing container 10 is located inside the holding member 23, and at this position, the toner is supplied to the inlet of the toner receiving portion 19 integrated with the holding member 23. . Although the toner receiving portion 19 is projected more rearward than the other portion of the holding member 23, the portion other than the toner receiving portion 19 of the holding member 23 is disposed more frontward than the main body panel of the image forming apparatus. Have been. On the back side of the main body panel of the image forming apparatus, various transfer rolls for transferring an image forming object such as paper, the above-described transfer device, and the like are arranged. That is, the toner supply container 1
A supply port 18 that communicates with the toner receiving unit 19 and the developing device 4 is located on the front side of the main body panel of the image forming apparatus, and the transport roll and the transfer device are located on the back side of the main body panel.

A-2. Driving System of Developing Unit and the Like As shown in FIG. 2, a toner agitator (transporting means) 25 is disposed inside each toner supply container 10. The toner agitator 25 is formed by forming a metal wire having a wire diameter of about 1 to 2 mm into a spiral shape having a winding diameter of about 40 mm and a pitch of about 40 mm. The inner diameter of the toner supply container 10 is set to about 45 mm. Further, a toner auger ( toner flow preventing means) 26 is provided inside each toner receiving portion 19. The toner auger 26
The resin is formed in a screw shape having an outer diameter of about 12 mm and a pitch of about 10 mm. The toner receiving section 19
Has an inner diameter of about 13 mm.

In FIG. 3, reference numeral 27 denotes a transmission clutch. Driving force is transmitted to the transmission clutch 27 from a drive motor (not shown) by a timing belt, whereby the developing roll 9, the stirring screws 7 and 8, and the toner agitator 25 are rotated. The transmission clutch 27 is fixed to a main body cabinet of the image forming apparatus, and a gear 28 is fixed to a rotation shaft of the transmission clutch 27 via a one-way clutch. Gears 29 and 30 are fixed to the shaft of the developing roll 9. When the developing roll 9 is adjacent to the photosensitive drum 12 (see FIG. 2), the gear 28 meshes with the gear 29. Gears 33, 32, and 35 are fixed to shafts of the stirring screws 7, 8 and the toner agitator 25, respectively. Further, the gear 30 always meshes with the idler gear 31, the idler gear 31 meshes with the gear 32, and the gear 32 meshes with the gear 33. The gear 35 is
It meshes with the idler gear 31 via a gear train 34 to be interlocked.

Therefore, when the transmission clutch 27 is driven and the developing roll 9 is rotated to supply the toner to the photosensitive drum 12, the stirring screws 7, 8 and the toner agitator 25 are also rotated in conjunction. The rotation direction of the stirring screws 7 and 8 in this case is as described above. In this case, the toner agitator 25 is rotated in the direction indicated by the arrows in FIGS. As a result, the toner in the toner replenishing container 10 is given a conveying force to the front side, that is, the replenishing port 18 side, as indicated by the dashed arrow in the drawing, and the toner is transferred from the toner replenishing container 10 to the toner chamber 20. Transported to

On the other hand, the shaft 26a of the toner auger 26 in the toner chamber 20 is driven by a drive motor (not shown) separate from the developing roll 9 and the like. The corresponding developing roll 9 rotates to transfer the toner to the photosensitive drum 1.
2, the toner auger 26 is rotated in the direction indicated by the arrow C, transports the toner in the direction indicated by the dashed arrow in FIG. 3, and drops into the housing 6 of the developing device 4 through the supply port 21.

As described above, when the developing roll 9 rotates to supply the toner to the photosensitive drum 12, the corresponding toner agitator 25 always transports the toner from the toner supply container 10 to the developing device 4, and The toner density on the body drum 12 does not become insufficient.

However, a drive motor for driving the toner auger 26 is controlled by a control device (not shown) so as to drive the toner auger 26 intermittently. The control device adjusts the driving time of the toner auger 26 according to the density of the patch formed on the photosensitive drum 12. Here, the patch is used to form an actually required image beforehand.
This is a toner image formed on the photosensitive drum 12 for a density test.

As shown in FIG. 3, the toner chamber 20 is elongated, and the supply port 18 and the supply port 21 are separated in the axial direction, so that the toner does not pass through the toner chamber 20 without resistance. It is impossible. Further, the inner diameter of the toner chamber 20 is formed smaller than that of the toner supply container 10. Therefore, the toner agitator 2 corresponding to the upstream side
As long as 5 to a certain amount or more of toner is being conveyed, toner is accumulated in the toner chamber 20. Therefore, the amount of the toner supplied to the developing device 4 is controlled by the driving time of the toner auger 26, whereby the amount of the toner supplied from the developing roll 9 to the photosensitive drum 12, and consequently, the density of the image to be formed is reduced. Controlled.

Conventionally, in an image forming apparatus, as disclosed in the above-mentioned JP-A-61-95370,
A large amount of toner in the toner supply container was once accumulated in a large toner chamber. Between the toner chamber and the developing device,
A shutter plate is provided, the degree of opening of the shutter plate is adjusted according to the density of the patch, and toner is freely dropped from the toner chamber to the inside of the developing device to supply the toner. In this case, the size of the toner chamber becomes large, and the space for the developing device is taken up. In a rotary developing device, when the entire developing device is rotated, the toner is agitated inside the toner chamber and inside the replenishing container, and the thickness tends to be uniform. When this happens, the toner near the replenishing port of the replenishing container decreases, and after the toner starts to be supplied from the developing device to the photosensitive drum, the toner rapidly decreases in the developing device. There is a case where an image having a desired density cannot be obtained because supply of toner to the inside cannot be performed in time.

However, in the present embodiment, the toner chamber 20 is made extremely small, whereby the cross-sectional area of the toner path from the toner supply container 10 to the developing device 4 is reduced, and the toner auger 26 is provided inside the toner chamber 20. By controlling the toner auger 26 to intermittently drive the toner when the developing roll 9 supplies the toner, as long as the toner is in the toner chamber 20, the amount of the toner to be supplied to the photosensitive drum 12 and thus the toner is formed. The image density is uniquely determined by the driving time of the toner auger 26.

When the corresponding developing roll 9 is driven, the toner agitator 25 is driven in synchronism with the driving, and the toner is conveyed toward the replenishing port 18. The toner is always supplied from the supply container 10, and the toner in the toner chamber 20 runs short on the way, and then the toner in the housing 6 runs short.
The occurrence of insufficient image density is reduced.

Further, a rotating toner agitator 25 is disposed inside the toner supply container 10, and the toner in the toner supply container 10 is conveyed by the toner agitator 25, so that the toner in the toner supply container 10 is almost left. It is possible to use up without. Therefore, if the toner supply container 10 is disposable, the amount of waste toner is extremely small. If the toner supply container 10 is recycled, the residual toner adheres to the toner supply container 10 during repeated use. Is prevented.

The pitch of the toner agitator 25 is considerably long, and the wire diameter of the toner agitator 25 is extremely small as compared with the inner diameter of the toner supply container 10. Therefore, when the toner is accumulated in the toner chamber 20 as described above, when the toner is stagnant at the supply port 18, even if the toner agitator 25 is rotated, the toner agitator 25 is attached to the toner in the toner supply container 10. It slips against it and gives no compressive force to it. Therefore, the toner is prevented from sticking in the toner supply container 10.

Then, the photosensitive drum 1 is transferred from another developing unit 4 to the photosensitive drum 1.
When the developing device 1 is rotated in the direction of arrow B in FIG. 2 to supply toner to the developing roller 2, the gear 28 and the gear 29 are disengaged from each other, and the developing roller 9 and the stirring screws 7, 8 are disengaged.
No driving force is applied to the toner agitator 25. When the developing device 1 rotates, the toner auger 26 is not driven by the drive motor.

A-3. FIG. 7 is a perspective view showing one holding member 23. FIG. As shown in the figure, the holding member 23 is formed in a substantially sector shape with a central angle of 90 °. The holding hole 14 is formed in a cylindrical shape, and the length of the portion where the holding hole 14 is formed in the axial direction is larger than the thickness of other portions of the holding member 23. The upper side in the figure is the front side, and the lower side is the back side. An arc-shaped concave portion 4 is provided on the front side of the inner peripheral surface of the holding hole 14.
0, 41, 42 and 43 are formed.

The recess 40 and the recess 41 are formed so as to be continuous, and the recess 41 is formed in the toner receiving portion 19.
Of the side wall. In the drawing, reference numeral 46 denotes a hole for receiving the shaft of the toner auger 26 in the toner receiving portion 19. A pair of L-shaped rails 63 are formed in the recess 41, and a toner chamber shutter 64 is engaged with these rails 63. The toner chamber shutter 64 is slidable along the rail 63. When the toner chamber shutter 64 is in the concave section 41, it closes the toner intake of the toner chamber 20. It is designed to open. Note that, as shown in FIG. 1, a protrusion 44 is formed in the recess 40.

The recess 41 and the recess 42 are formed so as to be continuous, but the recess 41 has a larger outer diameter than the recess 42. Three pins 48 protrude from the recess 42. At the time of molding, four of these pins 48 are formed at equal intervals, and one of them is left after being broken off. In this case, which pin 48 is to be cut off differs for each of the four toner supply containers 10. Further, on the inner peripheral surface of the holding hole 14, at a distance from the recess 43,
A narrow groove 49 is formed. The concave groove 49 has a trapezoidal cross section.

FIG. 6 is a perspective view showing the toner supply container 10. The supply port 18 is formed at the front end of the toner supply container 10 as described above. The toner supply container 10 is provided with a convex wall (not shown) so as to surround the supply port 18. Further, the toner supply container 10 is provided with a rail 50 which is integral with the convex wall. A shutter 51 is engaged with these rails 50 so that the supply port 18 can be opened and closed. Further, a ridge 58 is formed at the end on the far side of the toner supply container 10.

As shown in FIG. 5, the shutter 51 is in the shape of a circular arc plate, and has a convex wall 52 having an L-shaped cross section at both ends of its inner peripheral surface.
Is formed. Although not shown, the rail 50 of the toner supply container 10 has an L-shaped cross-section so as to be fitted into the sliding groove 53, so that the shutter 51
Are slidable along the circumferential direction of the toner supply container 10. The rotation of the shutter 51 or the toner supply container 10 opens or closes the supply port 18. A stopper 54 is formed at one end of the inner peripheral surface of the shutter 51, and the shutter 51 is connected to the supply port 18.
Is closed, the stopper 54 comes into contact with a convex wall (not shown) around the supply port 18. Further, a convex portion 55 (second engaging portion) is formed on a side end surface of the shutter 51. The protrusions 55 are formed at different positions for each of the four toner supply containers 10.

This shutter 51 is used for the toner supply container 1
0 is attached to the holding hole 14, the concave portion 42 of the holding hole 14
It is designed to fit in. As shown in FIG.
Since the outer diameter of the concave portion 42 is smaller than the concave portion 41 and the concave portion 43, when the shutter 51 is mounted on the concave portion 42, the shutter 51 cannot move in the circumferential direction of the holding hole 14. However, the toner replenishing container 10 itself can rotate around the axis, thereby relatively replenishing the replenishing port 1.
8 is opened.

Further, when the toner supply container 10 is mounted in the holding hole 14, the convex portion 55 of the shutter 51
2 enters a space (first engagement portion) 56 where the pin 48 is not provided upright. Here, as described above, the positions of the three pins 48 and the formation positions of the protrusions 55 are different for each of the four toner supply containers 10, and the positions of the toner supply containers 10 corresponding to the holding holes 14 are different. Even if another toner supply container 10 is inserted,
Is not completely inserted into the holding hole 14.

As shown in FIG. 4, a ridge 57 is formed at the front end of the outer peripheral surface of the toner supply container 10. An elongated knob (operation unit) 60 is projected from the front end surface of the toner supply container 10. When the toner supply container 10 is mounted in the holding hole 14, the toner supply container 1
After the user inserts the "0" into the holding hole 14, the user grips the knob 60 to rotate the toner supply container 10 around the axis. In FIGS. 1 and 4, reference numeral 61 indicated by a virtual line indicates a projection provided on the front cover of the main body cabinet of the image forming apparatus. As shown in FIG.
The front cover 62 is located closer to the main body than the knob 60, but the projection 61 is located closer to the back than the knob 60.

Therefore, in the state shown in FIG.
The front cover 62 is not closed because the protrusion 61 collides with 0, and in the state shown in FIG. 1, the knob 60 retreats from the protrusion 61 and the front cover 62 can be closed. When the front cover 62 is not closed, this is detected by mechanical or electrical detection means, and the fact is displayed on a display unit (not shown) of the image forming apparatus. Note that the projection 61 of the front cover 62 does not need to be a perfect circle as shown in FIGS. 1 and 4, as long as the function described above can be performed with respect to the knobs 60 of all the toner supply containers 10. It may be scattered along a circle shown by a virtual line. That is, the protrusion 61 shown in FIG.
Is a schematic one.

B. Operation of embodiment B-1. Next, a procedure for attaching the toner supply container 10 to the holding hole 14 will be described. First, the user turns the toner supply container 10 in the direction shown in FIG.
Into the corresponding holding holes 14. At this time, the protrusion 58 of the toner supply container 10 is guided by the concave groove 49 of the holding hole 14, and the toner supply container 10 is pushed forward so that the shutter 51 is located in the concave portion 42. In this case, supply port 1
Reference numeral 8 denotes a state closed by the shutter 51.

It should be noted that which toner supply container 10 is to be inserted into each holding hole 14 is predetermined.
If the toner supply container 10 is correctly inserted into the holding hole 14,
The protrusion 55 of the shutter 51 of the toner supply container 10 enters a space 56 without the pin 48.

Next, the toner supply container 10 is rotated by a predetermined angle in the direction indicated by the arrow in FIG. When the toner replenishing container 10 is rotated in this way, as shown in FIG. 1, the ridge 57 of the toner replenishing container 10 gets over the protrusion 44, and a small resistance force at this time is sensed by the user. In addition, as shown in FIG. 1, the projections 57 of the toner supply container 10 engage with the protrusions 44 of the holding hole 14 in this manner, so that the toner supply container 10 cannot be easily moved.

When the toner supply container 10 is rotated, the supply port 18 of the toner supply container 10 moves to the toner receiving portion 19 while the shutter 51 remains in the concave portion 42. In this case, the sliding groove 53 of the toner supply container 10
Engage with the rail 63 in the holding hole 14. further,
As the supply port 18 moves, the toner chamber shutter 64 having the concave portion 41 is pushed by the convex wall around the supply port 18.
Is also moved. Thus, the toner supply container 1
The supply port 18 is opened by the relative rotation of the shutter 0 and the shutter 51, and the inlet of the toner chamber 20 is also opened by the movement of the toner chamber shutter 64. Therefore, FIG.
As shown in (1), the supply port 18 communicates with the toner chamber 20 of the toner receiving section 19, from which toner can be supplied to the toner chamber 20.

When the amount of toner in the toner supply container 10 becomes small and the toner supply container 10 is to be replaced, the user rotates the attached toner supply container 10 counterclockwise from the state shown in FIG. Since only a small portion of the ridge 44 of the holding hole 14 and the ridge 57 of the toner supply container 10 are engaged with each other, if a large force is applied, the toner supply container 10 can be rotated in this manner. Can be. As a result, the toner supply container 10 is again placed in the holding hole 14 as shown in FIG.
The supply port 18 is closed by the shutter 51 in the recess 42, and the user can pull out the toner supply container 10 from the holding hole 14. The holding hole 1 is pressed by the ridge 57 of the toner supply container 10.
4, the toner chamber shutter 64 is pushed back, whereby the inlet of the toner chamber 20 is also closed.

As described above, according to the present embodiment, the shutter 51 is opened with the operation of holding the toner supply container 10 in the holding hole 14, and the shutter 5 is opened before that.
1, the supply port 18 is closed, so that the supply port 18 of the toner supply container 10 can be kept from being exposed.
Moreover, the shutter 51 is not opened simply by inserting the toner supply container 10 into the holding hole 14, and the shutter 51 is opened only by rotating the toner supply container 10 in the holding hole 14.

After the toner supply container 10 is removed from the holding hole 14 after use, the toner supply container 10 is rotated once so that the shutter 51 is closed, so that the supply port 18 is not exposed. The toner supply container 10 can be removed. In this way, it is possible to reduce the leakage of toner when the toner supply container 10 is attached and detached, and it is possible to reduce the possibility that the clothes and hands of the image forming apparatus and the user are stained.

As shown in FIG. 3, the movement of the toner from the toner supply container 10 to the toner receiving portion 19 is performed inside the holding member 23. The holding member 23 other than the toner receiving portion 19 protruding to the rear side is located on the front side of the main body panel, and a transport roll and a transfer device for transporting an image forming object such as paper are located on the rear side of the main body panel. Therefore, even if the toner leaks from the replenishing port 18 after the toner replenishing container 10 is mounted, the transfer roll and the transfer device are prevented from being contaminated by the toner, and the dropped toner can be easily cleaned. It is.

Further, if a toner receiver for receiving the toner dropped below the developing device 1 is provided, the above effect can be further enhanced. Conventionally, in a rotary developing device, when the developing device is rotated, the leaked toner falls, and this may contaminate the transfer roll and the transfer device. ,
This defect can be eliminated.

The supply port 18 is provided on the front side of the image forming apparatus, and a knob 60 for rotating the toner supply container 10 is formed on the front end surface of the toner supply container 10. Therefore, the distance between the knob 60 and the shutter 51 and the supply port 18 is extremely short. Since the toner supply container 10 is disposed so as to extend from the front side to the rear side of the image forming apparatus, the shutter 51 and the supply port 18 are provided on the rear side of the image forming apparatus, contrary to the embodiment. When the knob 60 is twisted to rotate the toner supply container 10, a large torsional distortion occurs in the toner supply container 10, and there is no possibility that the supply port 18 is kept closed by the shutter 51. Not really. However, as in the present embodiment, the knob 60 and the supply port 1
8, the rotation angle of the knob 60 is effectively transmitted to the position where the supply port 18 is located, and the supply port 18 is surely opposed to the toner receiving portion 19 and the shutter 51 is opened. become.

The opening and closing operation of the shutter 51 is performed in accordance with the operation of attaching and detaching the toner supply container 10, specifically, the rotation operation of the toner supply container 10, so that the user is required to separate the operation of attaching and detaching the toner supply container 10. It is not necessary to open and close the shutter 51, and work can be easily performed with one hand. further,
When the toner supply container 10 is not rotated, that is, when the toner supply container 10 is not completely held in the holding hole 14, that is, when the supply port 18 is facing downward because the shutter 51 is closed. However, the attachment / detachment work of the toner supply container 10 is possible. For this reason, it is not necessary to rotate the developing device 1 about the rotation shaft 2 so that the supply port 18 faces upward. This also allows the toner replenishing device 10
Is extremely easy, and the plurality of toner supply containers 10 can be attached and detached in a short time.

Further, the toner receiving portion 1 is also provided in the holding hole 14.
The toner chamber shutter 64 closes the inlet of the toner supply container 9, and the toner chamber 20 is closed by the toner chamber shutter 64 regardless of the position of the developing device 4 until the toner supply container 10 is rotated. Therefore, leakage of toner from the toner chamber 20 is prevented.

In this embodiment, in order to form a color image, black, yellow,
Supply magenta and cyan toner. Which developing unit 4 supplies which toner, that is, which toner supply container 10 is inserted into each holding hole 14, is predetermined in view of the control of image formation. And FIG.
And the combination of the convex portion 55 of the shutter 51 and the space 56 of the holding hole 14 shown in FIG.
When the wrong toner supply container 10 is inserted into the holding hole 14, the projection 55 hits the pin 48, and the toner supply container 10 cannot be inserted deep into the holding hole 14. In addition, the sliding groove 53 of the toner supply container 10
However, the toner supply container 10 cannot be rotated because it does not match the rail 63 in the holding hole 14. Therefore, the user will notice an error in selecting the holding hole 14 into which the toner supply container 10 is to be inserted.

Further, in this embodiment, after the toner supply container 10 is inserted into the holding hole 14, the toner supply container 10 is rotated by a predetermined angle to completely hold the toner supply container 10 in the holding hole 14, and at the same time, the toner supply container 10 is picked up. The direction of 60 is made so as not to hit the projection 61 of the front cover 62.
When the rotation of the toner supply container 10 is insufficient, that is, when the shutter 51 is not sufficiently opened, the knob 61 of the toner supply container 10 hits the projection 61 and the front cover 62 is closed. Can not. This state is displayed on the display unit as described above, so that the user can know.

In this way, all the toner supply containers 1
It is possible to confirm whether or not the mounting of “0” is sufficient and whether or not the shutter 51 is completely opened. Then, the user is prevented from operating the image forming apparatus in a state where the shutter 51 is not completely opened.

B-2. The state of the toner during rotation of the developing device The operation of each component in the corresponding developing unit 4 when the developing roll 9 is adjacent to the photosensitive drum 12 is as described above, and thus is omitted. The state of the toner in the toner chamber 20 and the toner supply container 10 will be described.

As described above, in order to supply the toner to the photosensitive drum 12 with one developing device 4 and then supply the toner to the photosensitive drum 12 with the other developing device 4, the developing device 1 needs to have the configuration shown in FIG. In the direction of arrow B. Then, the engagement between the gear 28 and the gear 29 shown in FIG. 3 is broken, and the developing roll 9, the stirring screws 7, 8 and the toner agitator 2
No driving force is applied to 5. Also, the supply of the driving force to the toner auger 26 is stopped.

However, the rotation of the developing device 1 corresponds to a revolving motion for each developing device 4. Therefore,
In the toner supply container 10 and the toner receiving portion 19, when the developing device 4 is revolved in the direction of arrow B in FIG. 2, even if the toner agitator 25 and the toner auger 26 are at rest, the toner agitator 25 and the toner auger 26 The toner moves along the spiral.

The direction of the spiral of the toner agitator 25 is such that when the toner is rotated in the direction of the arrow in FIG. The direction of the arrow is clockwise, which is the same as arrow B. Therefore, when the developing device 4 is revolved in the direction of arrow B in FIG. 2, the toner is moved toward the supply port 18 along the spiral of the toner agitator 25 in the toner supply container 10. Therefore, the next time the toner is supplied by the corresponding developing unit 4, the toner quickly flows into the toner chamber 20, which is convenient.

If the toner agitator 25 is not provided, the toner in the toner supply container 10 tends to disperse from the vicinity of the supply port 18 when the developing device 1 rotates about the rotation shaft 2. ,
In particular, when the amount of toner in the toner supply container 10 becomes small, there is a concern that the amount of toner transported from the toner agitator 25 to the toner chamber 20 becomes insufficient. However, if the toner in the toner supply container 10 is moved toward the supply port 18 by the toner agitator 25, it is possible to prevent the toner transport amount from becoming insufficient, and it is possible to prevent the density of the formed image from becoming insufficient. The occurrence can be delayed.

The spiral direction of the toner auger 26 is
When the toner is rotated in the direction of arrow C in FIG.
The direction to move. The direction of arrow C is counterclockwise and opposite to arrow B. Accordingly, when the developing device 4 is revolved in the direction of arrow B in FIG. 2, the toner is moved toward the supply port 18 along the spiral of the toner auger 26 in the toner chamber 20.

If neither the toner chamber 20 nor the toner auger 26 is provided, when the developing device 1 rotates,
With the movement of the toner by the toner agitator 25, the toner may flow directly from the toner supply container 10 into the housing 6. In this case, when the supply of toner is started by the developing device 4 next, the toner supply amount becomes excessively large, and the image becomes darker than the density to be controlled.

However, in the present embodiment, when the developing device 1 rotates, the toner is given a conveying force along the spiral of the toner auger 26 in the direction indicated by the imaginary line, that is, toward the supply port 18. As a result, the above-described problem can be avoided. The toner is concentrated near the supply port 18 by both the toner agitator 25 and the toner auger 26. However, the pitch of the toner agitator 25 is considerably long, and the toner agitator 25 has a larger pitch than the inner diameter of the toner supply container 10.
Since the wire diameter is extremely small, even when the toner agitator 25 rotates at the supply port 18, the toner agitator 25 slides on the toner in the toner supply container 10 and does not apply a compressive force thereto. Therefore, the toner is prevented from sticking in the toner supply container 10.

C. 4. Modifications Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and various modifications as described below are possible. In the above-described embodiment, the supply port 18 is opened and closed by the shutter 51 by rotating the toner supply container 10 into the holding hole 14 and then rotating it by a certain angle.
After the toner supply container is once inserted into the holding hole along the axial direction, if the toner supply container is inserted with a stronger force, the shutter may come into contact with the stopper to open the supply port. . In this case, the shutter may close the supply port when the toner supply container is pulled back.

In the above embodiment, the shutter 51
Is held in the recess 42 of the holding hole 14 so that the toner supply container 10 rotates to open and close the supply port 18 of the toner supply container 10. For example, the shutter 51 is urged to the toner supply container 10. A spring is provided so that when the toner supply container 10 is not mounted, the shutter 51 is connected to the supply port 18.
Can be closed.

In the above embodiment, the toner supply container 10 is erroneously inserted into another holding hole 14 due to the combination of the space 56 of the holding hole 14 without the pin 48 and the convex portion 55 of the shutter 51 of the toner supply container 10. Although the mounting is prevented, in this case, if the corresponding holding hole 14 and the toner supply container 10 have an engaging portion that engages with each other, an engaging portion of another form may be used. Good.

[0075]

As described above, according to the developing device of the image forming apparatus according to the first aspect, it is possible to reduce the leakage of toner when the toner supply container is attached and detached. There is less risk of soiling the user's clothes and hands. Further, the user can easily attach and detach the toner supply container with one hand. Further, it is possible to attach and detach a plurality of toner supply containers without taking time. Furthermore, a developing device
When the toner is supplied to the image carrier by
Can be prevented from becoming too large, and
Can be prevented.

According to the developing device of the sixth aspect, the toner
-Until the operation of holding the supply container in the holding unit is completed,
The second shutter closes the inlet of the developing device,
No matter where the imager is, toner leakage from the developer
Is prevented.

[Brief description of the drawings]

FIG. 1 is a front view showing a developing device of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the developing device.

FIG. 3 is a development view showing a rotating member in one developing device of the developing device and a driving system thereof.

FIG. 4 is a front view showing a state before the toner supply container of the developing device is completely mounted.

FIG. 5 is a perspective view showing a shutter of a toner supply container of the developing device.

FIG. 6 is a perspective view showing a toner supply container of the developing device.

FIG. 7 is a perspective view showing a holding member for holding a toner supply container of the developing device.

[Explanation of symbols]

1 developing device, 2 rotating shaft, 4 developing device, 6 housing,
7, 8 stirring screw, 9 developing roll (supply means),
Reference Signs List 10 toner supply container, 11 supply outlet, 12 photosensitive drum (development target), 14 holding hole, 18 toner supply container supply port, 19 toner receiving section, 20 toner chamber, 21 toner chamber supply port Entrance, 23 holding member (holding section), 25 toner agitator (transporting means), 2
6 toner auger ( toner flow preventing means), 27 transmission clutch, 48 pin, 51 shutter, 55 convex part (second engaging part), 56 space (first engaging part), 60 knob (operation means), 61 Front cover projection, 62 Front cover , 64 Toner chamber shutter (second shutter)

Continuation of front page (56) References JP-A-6-324565 (JP, A) JP-A-6-149047 (JP, A) JP-A-4-31884 (JP, A) JP-A-4-185355 (JP) JP-A-4-164649 (JP, A) JP-A-63-15752 (JP, A) JP-A-63-86652 (JP, U) JP-A-2-95052 (JP, U) 5-33163 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/08 G03G 15/01 113

Claims (4)

(57) [Claims] A plurality of developing units disposed around the rotating shaft, each having a toner inlet and a supply outlet; and a plurality of developing units arranged adjacent to the developing units, respectively. A developing device for an image forming apparatus, comprising: a toner supply container having a supply port capable of communicating with an inlet of a container; and a holding unit attached to the rotating shaft to detachably hold the toner supply container. The replenishing container is provided with a shutter for opening and closing the replenishing port. With the operation when the toner replenishing container is held by the holding part, the shutter is opened to open the replenishing port to the inlet of the developing device. And a first spiral body is provided in the toner supply container.
A configured transport means is provided, wherein the transport means
At this time, the first spiral body is driven to rotate, and
Of the toner in the toner supply container by the first spiral
Conveyed toward the inlet of the developing device, and
While the plurality of developing devices revolve around the center, the first screw
The rotating body revolves with the developing device without being driven to rotate
By doing so, the toner in the toner supply container is
The toner supply container is moved toward the supply port.
Between the inlet and the second spiral body
Means for preventing toner flow are provided.
Means for rotating the second spiral during development,
The second spiral body driven in rotation is directed toward the inlet.
And transports the toner, and the plurality of current
While the imager revolves, the second spiral is driven to rotate.
By revolving with the developing unit without
A developing device for applying a conveying force in a direction opposite to that of the developer during development. 2. The current supply outlet of the developing device,
Supply means for supplying the toner in the imager to the development target is provided.
During the development, the supply means of the corresponding developing device;
And the conveyance means of the toner supply container corresponding to
2. The developing device of the image forming apparatus according to claim 1, wherein:
Place. 3. The developing device has a cover that can be opened and closed.
The toner supply container is disposed in the image forming apparatus
When holding the toner supply container, the toner supply container is
By moving the shutter within the holding unit, the shutter
The toner is provided on the cover side of each toner supply container.
-An operation unit for moving the supply container inside the holding unit
Projecting, and at least one of the shutters is incompletely opened
When closing the cover, the shutter
Characterized in that the corresponding operation unit is obstructed.
A developing device for an image forming apparatus according to claim 1. 4. A first engaging portion provided on each of the holding portions.
Is provided, and each of the toner supply containers has a second
An engagement portion is provided, and a corresponding first engagement portion and a second engagement portion are provided.
Claims wherein only portions are engaged
Item 4. A developing device of the image forming apparatus according to any one of Items 1 to 3
Place.