JPH08137227A - Toner supply device - Google Patents

Abstract

PURPOSE: To easily exchange a toner cartridge, to lighten a burden imposed on a user and to narrow attaching space by providing plural toner cartridges and a toner carrying tube for carrying toner to a developing device. CONSTITUTION: This toner supply device 50 is provided with toner cartridge housing parts 52a and 52b to which two toner cartridges 50a and 50b of good size to be handled with one hand are respectively and individually attached. Toner carrying-out ports 51 a and 51b are formed in the respective toner cartridges 50a and 50b. Furthermore, the toner carrying tube 62 is provided with two branched tubes 62a and 62b which are joined halfway and the branched tubes 62a and 62b are respectively connected to the toner carrying-out ports 51a and 51b. The main tube 62c of the toner carrying tube 62 is provided with an auger 62e carrying the toner coming by way of the branched tubes 62a and 62b in a direction shown by an arrow 62d, and the toner is carried to the developing device by the auger 62e.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner replenishing device for replenishing toner to a developing device provided in an image forming apparatus such as an electrophotographic copying machine or a printer.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus using an electrophotographic system has been widely spread. This electrophotographic image forming apparatus normally charges a drum-shaped image carrier (photosensitive drum) uniformly, and emits light carrying information of an image recorded on a document to the photosensitive drum. The electrostatic latent image is formed on the photosensitive drum by irradiating the surface of the photosensitive drum, and the electrostatic latent image is developed with a developer (toner), and the developed image is directly transferred to a sheet through a transfer drum or the like. Is a device that obtains a printed (copied) image by performing. The electrophotographic image forming apparatus includes a developing device that develops the electrostatic latent image with toner. Further, the toner is a consumable item, and therefore, there is also one including a toner replenishing device for replenishing the developing device with the toner. This toner replenishing device is usually provided with a toner cartridge in which toner is stored. When the toner stored in the toner cartridge is replenished in the developing device and is exhausted, the image forming apparatus is stopped and the toner cartridge in which toner is depleted. Is replaced with a new toner cartridge in which toner is stored, the toner can be constantly replenished to the developing device, and the image forming apparatus can be used again.

In recent years, electrophotographic copying machines and printers for users, which are extremely frequently used and consume a large amount of toner, have been developed. In such a device, as much toner as possible is stored in one toner cartridge. If it is possible to do so, not only the number of times the toner cartridge needs to be replaced is reduced, but also the stoppage of the copier, printer, etc. is reduced, which is desirable in reducing the burden on the user who is not accustomed to handling the copier or the like.

However, if a large amount of toner is stored in one toner cartridge, the toner at the bottom of the toner cartridge is likely to coagulate. Therefore, the large amount of toner stored in the toner cartridge is agitated by a large output motor. There is a problem that an agitating device is required. As a technique for solving this problem, Japanese Patent Laid-Open No. 2-277083
In the publication, a toner server (cartridge housing) in which a plurality of toner cartridges each storing toner is replaceably mounted is used, and the toner in one toner cartridge among the plurality of toner cartridges is sampled. Once the toner is stored in a tank called a tank, the toner is replenished from the sump tank to the developing device, and before the toner in the sump tank runs out, other toner cartridges that store toner automatically There is disclosed a technique of replenishing toner to a sump tank to prevent the toner from coagulating and reduce the frequency of toner cartridge replacement.

However, this technique requires a sump tank for temporarily storing the toner in the toner cartridge after the toner in the toner cartridge is taken out from the toner cartridge. Therefore, a space corresponding to the sump tank is required and the toner is stored. There is a problem that a device for automatically replenishing the toner from another toner cartridge to the sump tank is complicated. or,
Japanese Unexamined Patent Publication No. 2-201393 discloses a technique in which a plurality of large toner replenishing devices each having a toner remaining amount detecting means are provided, and the plurality of toner replenishing devices are used in a predetermined cycle. However, in this technique, there is a problem that the cost is high because each toner replenishing device is provided with a toner remaining amount detecting means, and that each toner replenishing device is large, it is difficult to handle and the operability is poor. is there.

[0006]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention makes it possible to easily replace a toner cartridge to reduce the burden on the user and improve the operability.
An object of the present invention is to provide a toner replenishing device that can be mounted in a narrow space.

[0007]

To achieve the above object, a toner replenishing device of the present invention forms a latent image on an image carrier, develops the latent image with toner, and develops the developed image on a transfer material. In a toner replenishing device for replenishing toner to a developing device for developing a latent image formed on the image carrier in an image forming apparatus for transferring, toner is stored and discharging means for discharging the stored toner to the outside while stirring. A plurality of toner cartridges each of which is freely attached to and detached from the image forming apparatus, and a plurality of toner cartridges connected to the plurality of toner cartridges and joined together on the way to the developing device. A toner carrying pipe for carrying the toner discharged from the toner cartridge to the developing device is provided.

Here, it is preferable to provide a sensor for detecting the presence / absence of toner after the toner conveying pipes merge.

[0009]

According to the toner replenishing device of the present invention, since a plurality of toner cartridges having the ejecting means can be freely attached to and detached from the image forming apparatus, the toner cartridges can be easily replaced, the burden on the user is reduced, and the operability is reduced. Is good. In addition, since the toner discharged from the toner cartridge mounted in the image forming apparatus is conveyed to the developing device by the toner conveying pipe, a container for temporarily storing the toner discharged from the toner cartridge is not required. Since the toner cartridge of (1) doubles as the conventional sump tank, the toner replenishing device can be installed in a narrow space.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the toner replenishing device of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing an outline of an electrophotographic apparatus using the toner replenishing device of the present invention. The rotating drum-shaped image carrier 12 uniformly charged by the charger 10 is exposed by the exposure beam 18 deflected by the polygon mirror 16 of the laser type exposure device 14, thereby forming a latent image on the image carrier 12. Are formed, and the latent image is developed by the developing device 20 to form a toner image. Developer 2
0 is a developing roll 22 that carries toner to a developing position where a latent image is developed, and causes the toner to fly to the image carrier 12 for development, and a layer that regulates the thickness of the toner carried by the developing roll 22. A thickness regulating member 24 is provided. The formed toner image is transferred by the paper carrying device 26 to the paper carried to the transfer device 28. The sheet on which the toner image is transferred is conveyed to the fixing device 32 via the conveying belt 30. The fixing device 32 includes a fixing roll 34 and a pressure roll 36, which are heated and pressed from above and below to fix the toner on the paper. On the other hand, the image carrier 12 after the transfer is cleaned by the cleaning blade 38, and the toner remaining on the image carrier 12 is removed. The cleaned image carrier 12 is irradiated with light by a charge eliminating lamp (not shown) to remove charges, and then the charger 1 again.
It is charged at 0.

A toner replenishing device for replenishing the developing device 20 with toner will be described with reference to FIG. The toner replenishing device 50 is provided with a toner cartridge accommodating portion 52a, in which two toner cartridges 50a and 50b each having a size suitable for being handled by one hand can be individually mounted.
52b is provided. Each toner cartridge 50a, 5
Toner outlets 51a and 51b are formed at 0b, and the toner outlets 51a and 51b are configured to open when the toner cartridges 50a and 50b are attached to the toner cartridge housing portions 52a and 52b. Inside the toner cartridges 50a and 50b, agitators 54a and 54b (an example of a discharging unit according to the present invention) are provided.
And agitator gears 53a, 53b for rotating the agitators 54a, 54b. The agitator gears 53a, 53b are driven by an external motor 56 to drive transmission gears 58, one-way clutches 60a, 60b, and one-way clutches 60a, 60b. Gear 6 connected to
The agitators 54a and 54b are rotated via the rollers 1a and 61b, whereby the toner stored in the toner cartridges 50a and 50b is agitated and the toner carry-out ports 51a and 51b.
It is discharged from b. The motor 56 is a motor that can rotate forward and backward freely, and the one-way clutches 60a and 60b are
The rotation directions for transmitting the driving force of the motor 56 to the agitators 54a and 54b are set to be opposite to each other. Therefore, for example, when the toner is carried out from the toner cartridge 50a, the motor 56 is rotated according to the transmission direction of the one-way clutch 60a. in this case,
The toner in the toner cartridge 50b is not carried out because the one-way clutch 60b does not rotate and the agitator 54b does not rotate.

The toner carrying pipe 62 is provided with two branch pipes 62a and 62b which join together on the way, and the two branch pipes 6 are provided.
2a and 62b are toner outlets 51a and 51b, respectively.
It is connected to the. The main pipe 62c of the toner conveying pipe 62 is provided with an auger 62e for conveying the toner having passed through the branch pipes 62a and 62b in a direction indicated by an arrow 62d, and the toner is conveyed to the developing device by the auger 62e. .

The toner carrying pipe 62 is provided with a sensor 64 for measuring the amount of toner passing through the toner carrying pipe 62, and the amount of toner passing near the sensor 64 of the toner carrying pipe 62 is measured. . The toner stored in the toner cartridge 50a is carried out and disappears,
When the sensor 64 detects that there is no toner passing near the sensor 64 (toner empty),
A control device (not shown) issues an instruction to the motor 56 to reverse its rotation direction, and immediately the agitator 54b of the toner cartridge 50b is rotated, and the toner starts to be discharged from the toner cartridge 50b. When the toner starts to be discharged from the toner cartridge 50b, a message prompting the user to replace the toner cartridge 50a with a new toner cartridge in which toner is stored is transmitted to the user via a user interface (not shown),
According to this message, the toner cartridge 50a is replaced with a new toner cartridge. Although the toner replenishing device 50 that automatically switches the cartridge is shown here, for example, the toner currently in use is provided to the user via a user interface (not shown) or the like according to the toner empty detection signal of the sensor 64. Instruct to switch the cartridge to the other toner cartridge,
It is also possible to configure so that the rotation direction of the motor 56 is switched by the user manually operating the changeover switch or the like. Further, the rotation direction of the motor 56 can be manually switched by providing a switching lever or the like for switching the path for transmitting the driving force of the motor 56 and mechanically switching the driving force of the motor 56 by this switching lever or the like. You can also In the above embodiment, the toner replenishing device provided with two toner cartridges is shown. However, by extending the toner carrying pipe, three or more toner cartridges are provided, and the arrangement of the plurality of toner cartridges is the same as that of the embodiment. The arrangement is not limited to the parallel arrangement as in 2, and can be freely arranged at an angle depending on the layout of M / C. Further, the means for transmitting power to the agitator is not limited, and a motor is individually provided, and it is also possible to switch a switch.

As described above, according to the toner replenishing device 50, the toner cartridges 50a and 50b are exchanged by attaching and detaching the toner cartridges 50a and 50b to and from the toner cartridge accommodating portions 52a and 52b. Makes it easy to replace the toner cartridge and reduce the burden on the user. In addition, the amount of toner passing through is measured by the sensor 64, and when the toner runs out in one of the toner cartridges, the toner is carried out from the other toner cartridge 50a, 50b and passed through the toner carrying pipe 62 to the developing device. Since it is replenished, peripheral devices such as sump tanks can be reduced. Further, by unifying the size of the toner cartridge accommodating portion among all the models such as the electrophotographic apparatus, the toner cartridges of the respective models can be shared. Furthermore, by arranging the toner transport pipe in a stretched state,
The toner cartridge accommodating portion can be formed at any place, the degree of freedom in layout is widened, and the entire machine can be downsized and flattened.

[0015]

As described above, the toner replenishing device of the present invention has good operability because the size of the toner cartridge can be easily replaced, and the image forming apparatus can be stopped even if the sump tank is not provided. Without letting
Also, it does not require a large space.

[Brief description of drawings]

FIG. 1 is a schematic view showing an outline of an electrophotographic apparatus using a toner replenishing device of the present invention.

FIG. 2 is a schematic configuration diagram showing an embodiment of a toner replenishing device of the present invention.

[Explanation of symbols]

 12 image carrier 20 developing device 50 toner supply device 50a, 50b toner cartridge 54a, 54b agitator 62 toner transport pipe

Claims (2)

[Claims] 1. A latent image formed on the image carrier is developed in an image forming apparatus for forming a latent image on the image carrier, developing the latent image with toner, and transferring the developed image to a transfer material. In a toner replenishing device for replenishing toner to a developing device, the toner is stored and has a discharging means for discharging the stored toner to the outside while stirring, and each of the plurality of toners is detachably attached to the image forming apparatus. A toner cartridge; and a toner transport pipe, which is connected to each of the plurality of toner cartridges and merges in the middle and is connected to the developing device to transport the toner discharged from the plurality of toner cartridges to the developing device. A toner replenishing device characterized by being provided. 2. A sensor for detecting the presence / absence of toner after merging the toner conveying pipes is provided.
The toner supply device described.