JP2002091143A - Toner replenishing device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner replenishing device and an image forming device where a path for toner of an appropriate size can be obtained without making a diameter of an inserting/extracting member to be a large diameter. SOLUTION: In the device, a nozzle 40 that is formed to be a tube that is inserted to/extracted from a toner storing container 20 and an air pump 30 feeding air inside the toner storing container 20 through the nozzle 40 are provided and the path 41 that is shared as an air path where the air that is fed inside the toner storing container 20 is passed and as a toner path where toner that is ejected from the toner storing container is passed is provided in the nozzle 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner replenishing apparatus and an electrophotographic image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, a toner container is a cartridge,
Since the bottle is made of a hard bottle such as a bottle, the disposal of the used container accompanying the replacement of the toner storage container has caused a great problem. In other words, the used toner container is collected by the manufacturer from the user, and recycled, reused,
Although the incineration process is performed, the container has a large capacity and requires a high distribution cost until it is collected.

Conventionally, there has been proposed a toner storage container in which the volume of the toner storage container can be reduced. However, when toner is replenished from the container by using a toner supply device, it is necessary to stably maintain the replenishing performance. Even when a container that cannot be reduced and whose volume can be reduced only at the time of transportation is used, problems such as toner contamination occur when transferring the toner, and it has not been put to practical use.

Further, in the conventional toner transfer technique, since the toner supply technique is based on mechanical auger means, the toner replenishing device and the toner storage container have to be installed integrally with the developing device or at a position very close to the developing device. . This complicates the structure of the toner replenishing device, hinders high cost, low productivity, and low maintenance of the machine.It is also difficult to secure and maintain the toner quality characteristics. There was also difficulty.

[0005] The applicant of the present invention blows air into the toner storage container to fluidize the toner and discharge it from the container.
A toner replenishing device for replenishing the discharged toner to the developing device using an air stream or a powder pump is not known but has been proposed.

This toner replenishing device has various advantages such as the setting position of the toner storage container irrespective of the position of the developing device, the use of a soft case for the container, and the prevention of unnecessary stress on the toner. It is equipped.

[0007]

However, the above-described toner replenishing device has some problems. For example, since the insertion / removal member inserted / removed into the container has a toner passage and an air supply passage, the toner passage becomes too narrow unless it has a certain diameter. Therefore, if the diameter of the insertion / removal member is increased, toner leakage from the seal valve will occur when the insertion / removal member is removed.

In view of the above problems, an object of the present invention is to provide a toner replenishing apparatus and an image forming apparatus which can provide a toner passage of an appropriate size without increasing the diameter of the insertion / removal member.

[0009]

In order to achieve the above object, the present invention provides a toner replenishing device for replenishing toner stored in a toner storage container to a developing device. An air passage through which the air supplied into the toner storage container passes through the insertion / removal member and air supply means for supplying air into the toner storage container via the insertion / removal member; And a passage which also serves as a toner passage through which the toner discharged from the toner storage container passes.

The present invention is effective when an opening / closing means for opening and closing the toner supply path is provided in the toner supply path from the air supply section of the air supply means to the entrance of the developing device. .

According to another aspect of the present invention, there is provided a toner replenishing device for replenishing toner contained in a toner storage container to a developing device. A member, air supply means for supplying air into the toner storage container through the insertion / removal member, and a suction-type powder pump for supplying toner stored in the toner storage container to the developing device, The insertion / removal member is provided with a passage that functions as an air passage through which air supplied into the toner storage container passes and a toner passage through which toner discharged from the toner storage container passes.

The present invention is advantageous in that the powder pump also functions as an opening / closing means for opening and closing a path provided in a toner supply path from the air supply section of the air supply means to the entrance of the developing device. It is a target.

Further, the present invention is effective when the toner supply path is closed by stopping the opening / closing means or the powder pump when the air supply means is operated.

Further, the present invention is effective when the operation of the air supply means is stopped when the toner supply path is opened by the operation of the opening / closing means or the powder pump.

Still further, according to the present invention, when the cumulative time of the toner supply time by the operation of the powder pump becomes equal to or longer than a predetermined time, air is supplied from the air supply means to the toner container. It is effective.

Further, the present invention is effective when the air supply unit and the toner supply unit are provided in the insertion / removal member, and the air supply unit is located above the toner supply unit.

Further, the present invention is effective when the air supply unit and the toner supply unit are provided in the insertion / removal member, and the toner supply unit is located above the air supply unit.

Further, the present invention is effective when the diameter of the air supply section from the air supply means is smaller than the diameter of the toner supply section. Furthermore, the present invention is effective when the air supply from the air supply unit to the toner container is supplied from the lowest position of the toner supply path.

Furthermore, the present invention is effective when the air supply from the air supply means to the toner container is opened and closed by an air valve. In order to achieve the above object, the present invention is characterized by comprising a toner supply device according to any one of claims 1 to 12.

It should be noted that the present invention provides a plurality of toner storage containers,
It is effective if a toner replenishing device and a developing device are provided. Further, the present invention is effective when air is supplied to each toner storage container by a single air supply unit.

Still further, according to the present invention, when air is supplied from the single air supply means to each toner storage container by an air valve provided for each toner storage container,
It is effective.

Further, the present invention is effective when the supply of air from the single air supply means is controlled so as not to be simultaneously supplied to the toner container two or more times.

[0023]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic diagram showing a color laser printer which is an example of an image forming apparatus according to the present invention. This color laser printer has a configuration in which a paper feed unit 2 is disposed at a lower portion of an apparatus main body 1 and an image forming unit 3 is disposed above the paper feed unit 2. The image forming unit 3 is provided with a transfer belt device that is arranged so as to be inclined such that the paper supply side is downward and the paper discharge side is upward. The transfer belt device 8 has an endless transfer belt 8a wound around a plurality of belt wheels, in this example, four belt wheels, and magenta (M) is sequentially arranged from the bottom on the upper running side of the transfer belt 8a. , Cyan (C),
Four image forming units 4 for yellow (Y) and black (Bk)
M, 4C, 4Y, and 4Bk are arranged in parallel.

FIG. 2 is an enlarged explanatory view showing a part of the image forming unit 4. As shown in FIGS. 1 and 2, each of the image forming units 4M, 4C, 4Y and 4Bk includes an image carrier. The photosensitive drum 5 is provided, and the photosensitive drum 5 is driven to rotate clockwise by driving means (not shown). Around the photoreceptor drum 5, a charging roll 6 as charging means, an optical writing unit where writing by laser light is performed by an optical writing device 7, and a developing device 1 as developing means
0, a cleaning device 9 is provided as cleaning means. The developing device 10 is a two-component developing device including a toner and a carrier, and toner corresponding to the consumed toner amount is replenished from the toner storage container 20 by a toner replenishing device. The toner replenishing device replenishes the image forming units 4M, 4C, 4Y, and 4Bk with the toner stored in the same number of toner storage containers 20.

As shown in FIG. 3, the developing device 10 is provided with a uniaxial eccentric screw pump which is a suction type powder pump 11 in the vicinity or integrally therewith. As shown in FIG. 4, the structure of the powder pump 11 is such that a rotor 12 made of an eccentric screw with a rigid material such as a metal and an elastic body made of rubber or the like have a two-screw shape. And a holder 1 made of a resin material or the like that wraps the stator 13 and forms a powder conveying path.
And 4. The rotor 12 is rotationally driven via a gear 16 integrally connected to a drive shaft 15 connected by a pin joint. Reference numeral 17 denotes an electromagnetic clutch, and the operation of the powder pump 11 is controlled by the clutch.

The tip of the holder 14, that is,
A toner suction unit 18 is provided at the right end of FIG. 3, and is connected to the toner suction unit 18 by a toner transfer tube 19 and a toner connection port 45 provided in a nozzle 40 serving as an insertion / extraction member described later. As the toner transfer tube 19, a flexible tube having a diameter of, for example, 4 to 10 mm and made of a rubber material having excellent toner resistance (for example, polyurethane, nitrile, EPDM, or silicon) is extremely used. Effective and flexible tubes can be easily piped in any direction, up, down, left and right. In the toner replenishing apparatus thus configured, a single-axis eccentric screw pump, which is a powder pump 11, is capable of performing a constant quantitative transfer at a high solid-gas ratio, and has an accurate toner proportional to the rotation speed of the rotor 12. Is known to be obtained. Therefore, when a toner replenishment command is issued due to image density detection or the like, the powder pump 11 operates to replenish the required amount of toner to the developing device 10.

On the other hand, the set section 50 provided in the image forming apparatus main body 1 in which the toner container 20 is set is configured as a unit separate from the developing apparatus 10. A nozzle 40 having a circular cross section which is inserted into and removed from the toner storage container 20 is provided upright on the set portion 50, and the toner storage container 20 is set to the setting portion 50 of the image forming apparatus main body 1 from above. The nozzle 40 provided in the setting section 50
A pointed member 44 having a conical cross section is provided at the upper portion by integral molding or fixing, and a passage 41 serving as an air supply path and a toner supply path is provided following the pointed member 44. The inside of the nozzle 40 has a single tube structure, and the passage 41 is bent at the lower end of the nozzle 40 to the left in the figure, and a tip end thereof is provided with a toner connection port 42 to which the toner transfer tube 19 is connected. I have. Passage 4
1 is provided with an air connection port 43 which is bent rightward in the figure above the toner connection port 42.

In the case of this embodiment, the air connection port 43 is
An air pump 30 as an air supply means is connected via an air transfer pipe 31. When the air pump 30 operates, the air transfer pipe 31
Air is blown into the toner container 20 via the passage 41. The air blown into the toner storage container 20 is fluidized while diffusing the toner by passing through the toner layer.

The toner storage container 20 is a back-in-box type having a deformable toner bag 21 for storing toner and an outer box 22 for storing the toner bag 21 and having greater rigidity than the bag. Have been. Toner bag 21
Is made of a single layer or multiple layers of a flexible sheet made of resin or paper such as polyethylene or nylon having a toner container of about 80 to about 20 μm. The toner bag 21 is formed by a blow molding method or the like. A base 23 made of resin or the like provided with a toner supply unit is fixed. The toner bag 21 has a hermetically sealed structure, and a base 23 at the bottom thereof has an elastic body as a self-closing valve.
A seal valve 24 preferably made of foam sponge or the like is provided. It should be noted that applying aluminum vapor deposition to the front or back surface of the sheet of the toner bag 21 is effective for measures against static electricity and moisture.

The toner replenishing device thus configured is
When the toner storage container 20 is attached to and detached from the image forming apparatus main body 1, a passage 41 is provided in the nozzle 40 that is inserted into and removed from the container, the air supply path also serving as a toner supply path.
Therefore, as compared with the case where the air supply path and the toner supply path are separately provided, the structure is simple, the manufacturing cost is greatly reduced, and the cross-sectional area of the passage 41 itself is large, so that toner clogging hardly occurs. Become. Further, in the present embodiment, since the air connection port 43 is provided above the toner connection port 42 in the nozzle 40, leakage of the toner to the air connection port can be reduced.

When the nozzle 40 has a single tube structure, the movement of the toner and the supply of the air cannot be performed at the same time. Therefore, the control is performed so that the movement of the toner and the supply of the air are not performed simultaneously, and a preferable control example will be described with reference to FIG.

In FIG. 4, the toner supply amount is determined by determining the ON time of the powder pump 11 based on the output of the T sensor for each print. When the determined toner replenishment is completed, the on-time of the powder pump 11 is integrated, and when the integrated time reaches a predetermined time, the air pump 30 is operated after the toner replenishment has reached the predetermined time, and the toner pump is operated. Air is supplied into the storage container 20. The supplied air amount is a fixed amount, and the accumulated time is reset.

By controlling the toner supply in this way,
Even when the nozzle 40 has a single tube structure, stable toner replenishment performance can always be ensured. Air pump 3
0 to supply air to the toner container 20
If the nozzle 40 has a single tube structure, air may be sent to the developing device 10 via the toner transfer tube 19 and the powder pump 11, but since the powder pump 11 is a single-axis eccentric screw pump, Since the toner transfer path is a closed path, such a problem does not occur. Furthermore, when toner is sent by air pressure without using a powder pump, an on-off valve (not shown) may be provided in the toner transfer path instead of the powder pump. In this case, an air valve is also provided in the air passage of the air pump 30, and when air is supplied to the toner storage container 20, the air valve is opened after closing the open / close valve to increase the internal pressure of the toner storage container to some extent.
If the on-off valve is opened after the air valve is closed, the toner can be replenished without sending the toner by the air pressure to the air pump side. When toner is supplied by air pressure, the toner storage container 20 needs to be a closed container. However, when the powder pump 11 is used, it is preferable to provide a filter capable of adjusting the air pressure in the container.

In this control, the operation time of the air pump 30 is shorter than the operation time of the powder pump 11. Therefore, when four image forming units 4 are provided as in the present embodiment, it is not necessary to provide the air pump 30 for each toner supply device, and only one air pump 30 is possible. FIGS. 5 and 6 show control examples of the control unit 30.

FIG. 5 is a diagram showing the relationship between the air pump 30 and each of the toner storage containers 20M, 20C, 20Y, and 20Bk. The air supply tube 31 from the air pump 30 includes four toner storage containers 20M, 20M. 20C, 20
Four tubes 32M, 32C, 32Y, and 32Bk are branched on the way so that air can be supplied to Y and 20Bk. Each of the branched tubes 32M, 32C, 3
Air valves 33M, 33C, 3
3Y and 33Bk are provided, and air is supplied only to the toner storage containers 20M, 20C, 20Y, and 20Bk connected to the air valves 33M, 33C, 33Y, and 33Bk that are turned on.

The control of such a configuration is as shown in FIG.
The air pump 30 is turned on for a time corresponding to the total amount of air supplied to each, and when the air pump 30 is on, the air valves 33M, 33C, 33Y, and 33Bk are turned on according to the amount of air to be supplied. open. At this time, two or more air valves 33M, 33C, 3
By controlling not to turn on the 3Y and 33Bk, a necessary amount of air can be supplied to each of the toner storage containers 20M, 20C, 20Y and 20Bk.

The toner replenishing device thus constructed can reduce the cost as compared with the case where a plurality of air pumps are provided. Moreover, since air is not supplied to the two or more toner storage containers 20M, 20C, 20Y, and 20Bk at the same time, the required amount of air can be supplied to each container with high accuracy. Further, also in this control, since the toner supply and the air supply are not performed at the same time, the nozzle 40 functions sufficiently with a single tube structure.

FIG. 7 is a sectional explanatory view showing another embodiment of the present invention. In this embodiment, the nozzle 40 has a toner connection port 42 provided above the air connection port 43.

With this configuration, the clogging of the toner in the nozzle 40 can be prevented by the air flow. Further, by making the diameter of the air connection port 43 smaller than that of the toner connection port 42, the air connection port 43 is formed.
Thus, it is possible to prevent the toner from leaking to the toner.

FIG. 7 is a sectional explanatory view showing another embodiment of the present invention. In this embodiment, the nozzle 40 has the toner connection port 42 provided above the air connection port 43.

With this configuration, toner clogging in the nozzle 40 can be prevented by the air flow. Further, by making the diameter of the air connection port 43 smaller than that of the toner connection port 42, the air connection port 43 is formed.
Thus, it is possible to prevent the toner from leaking to the toner.

FIG. 8 is an explanatory sectional view showing still another embodiment of the present invention. In this embodiment, the lowest position from the nozzle 40 to the powder pump 11, in this example, in the middle of the toner transfer tube 19. And a tube 31 of the air pump 30 is connected to the branch pipe.

With this configuration, the air pump 30
Is supplied from the lowermost position in the toner transfer path, so that it is possible to reliably prevent the path from being clogged with toner accumulated by its own weight at the lowermost position.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, but can be variously modified. For example, the cross-sectional shape of the nozzle is preferably circular as in the above embodiment,
Since it is not necessary to limit the shape to a circle, the shape may be a polygon, an ellipse, or a track. The configuration of the developing device to which the toner is replenished is arbitrary, and the present invention can be applied to a device using a one-component developer.

[0045]

According to the first and third aspects of the present invention, the insertion / removal member can have a single pipe structure, and the production cost of the member can be greatly reduced.

According to the second aspect of the present invention, it is possible to replenish the toner by air pressure even if a single-tube insertion / removal member is provided. According to the configuration of the fourth aspect, it is possible to prevent the air from the air pump from being sent into the developing device by the powder pump that urges the suction force to supply the toner to the developing device.

According to the fifth, sixth and seventh aspects, the toner can be reliably transferred by the powder pump.
According to the configuration of the eighth aspect, leakage of the toner to the air supply path can be reduced.

According to the ninth aspect, clogging of the toner in the insertion / removal member can be prevented. Claim 10
According to the configuration, the leakage of the toner to the air supply path can be reduced.

According to the eleventh aspect, toner clogging in the toner transfer path can be prevented. Claim 1
According to the configuration 2, it is possible to prevent the air from being sucked in through the air pump when the powder pump is operated.

According to the thirteenth aspect, it is possible to provide an image forming apparatus capable of supplying toner stably at low cost. According to the fourteenth to sixteenth aspects, it is possible to provide a color image forming apparatus capable of supplying toner stably at low cost.

According to the seventeenth aspect, a single air pump can reliably supply a necessary amount of air even if the supply destination is plural.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an overall configuration of a color image forming apparatus of the present invention.

FIG. 2 is an explanatory diagram showing an enlarged image forming unit in the color image forming apparatus of FIG. 1;

FIG. 3 is an explanatory sectional view showing an embodiment of the toner supply device of the present invention.

FIG. 4 is a timing chart showing a control example of a powder pump and an air pump.

FIG. 5 is an explanatory diagram of an air supply path showing another embodiment of the present invention.

FIG. 6 is a timing chart showing a control example of FIG. 5;

FIG. 7 is a sectional view of a nozzle showing another embodiment of the present invention.

FIG. 8 is an explanatory sectional view of a toner replenishing device according to still another embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 developing device 11 powder pump 20 toner container 30 air pump 40 nozzle 41 passage

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yoshio Hattori 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Takaaki Yanagisawa 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Inside Ricoh Company (72) Inventor Kazuhisa Sudo 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh Company (72) Inventor Shota Fujimori 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh Company (72) Inventor Motoki Hanada 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Co., Ltd. (reference) 2H077 AA02 AA12 AA18 AA25 AC11 DA13 DA78 DB02 GA04 GA12 3F047 AA01 CC11

Claims (17)

[Claims] 1. A toner replenishing device for replenishing toner stored in a toner storage container to a developing device, comprising: a tubular insertion / removal member inserted / removed into / from the toner storage container; Air supply means for supplying air into the container,
A toner supply, wherein the insertion / removal member has an air passage through which air supplied into the toner storage container passes and a toner passage through which toner discharged from the toner storage container passes. apparatus. 2. The toner supply device according to claim 1, wherein an opening / closing means for opening and closing the toner supply path is provided in a toner supply path from an air supply unit of the air supply means to the entrance of the developing device. A toner supply device. 3. A toner replenishing device for replenishing toner stored in a toner storage container to a developing device, comprising: a tubular insertion / removal member inserted / removed into / from the toner storage container; An air supply unit for supplying air into the container; and a suction-type powder pump for supplying toner stored in the toner storage container to the developing device. A toner passage that serves as an air passage through which the supplied air passes and a toner passage through which the toner discharged from the toner storage container passes. 4. The toner supply device according to claim 3, wherein the powder pump opens and closes a path provided in a toner supply path from an air supply unit of the air supply unit to an entrance of the developing device. A toner replenishing device, which also functions as an opening / closing unit. 5. The toner supply device according to claim 1, wherein when the air supply unit is operated, the toner supply path is closed by stopping the opening / closing unit or the powder pump. A toner replenishing device characterized by being used. 6. The toner supply device according to claim 1, wherein when the toner supply path is opened by operation of the opening / closing means or the powder pump, the operation of the air supply means is performed. The toner supply device is stopped. 7. The toner replenishing device according to claim 3, wherein when the accumulated time of the toner replenishment time by the operation of the powder pump becomes equal to or longer than a predetermined time, the air supply unit supplies the toner replenishment time. Wherein a supply of air to the toner container is performed. 8. The toner replenishing device according to claim 1, wherein an air supply unit and the toner replenishment unit are provided on the insertion / removal member, and the air supply unit is located above the toner replenishment unit. A toner replenishing device which is located at a position. 9. The toner supply device according to claim 1, wherein an air supply unit and the toner supply unit are provided on the insertion / removal member, and the toner supply unit is located above the air supply unit. A toner replenishing device which is located at a position. 10. The toner supply device according to claim 1, wherein a diameter of an air supply unit from the air supply unit is smaller than a diameter of the toner supply unit. Replenishment device. 11. The toner supply device according to claim 9, wherein the air supply from the air supply means to the toner storage container is supplied from a lowermost position of the toner supply path. . 12. The toner supply device according to claim 1, wherein the air supply from the air supply means to the toner storage container is opened and closed by an air valve. apparatus. 13. An image forming apparatus comprising the toner replenishing device according to claim 1. Description: 14. The image forming apparatus according to claim 13, further comprising a plurality of toner containers, a toner replenishing device, and a developing device. 15. The image forming apparatus according to claim 14, wherein air is supplied to each toner container by a single air supply unit. 16. An image forming apparatus according to claim 15, wherein air is supplied from said single air supply means to each toner storage container by an air valve provided for each toner storage container. Forming equipment. 17. The image forming apparatus according to claim 15, wherein the supply of air from the single air supply unit is controlled such that the air is not supplied to the toner storage container in two or more at the same time. Image forming device.