JPH0710101A - Charging method for toner - Google Patents

Abstract

PURPOSE:To obtain a compact charging apparatus which increases a drop speed from a funnel to a container without requiring complex equipment by introducing gas in charging fine powder toner having large bridging property to improve flowability. CONSTITUTION:A charging apparatus 9 comprises a hopper 10 and an inlet 12 connected to the lower end thereof, while air suction ports 11 are provided on a side of the hopper 10. The charging apparatus 9 can charge fine powder by aerating it thereby improving flowability. The fine powder put in the charging hopper 10 is fluidized by supplying air from the air suction port 11. The air suction port 11 is provided on two or more portions, that is, a plurality of portions symmetrically on a circumference on the side for example at a middle part and a lower part of the hopper in order to facilitate the fluidization uniformly. The suction port is shaped in a mesh to allow uniform aeration. The fluidized fine powder is quantitatively supplied through the inlet 12 using a single-axis screw pump to a funnel part 13 at a high speed without flushing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filling method for filling a container with a fine powder, and more particularly to a filling method suitable for filling a container with toner used in an image forming apparatus.

[0002]

2. Description of the Related Art Many methods have been proposed as means for filling fine powder into a container. However, since the average particle size is fine and the adhesion and crosslinkability are large, bridging is easy and air is used. It has been considered that it is difficult to fill fine powder such as toner of an electrostatic copying machine having high fluidity and easily flushing at a high speed.

At present, an auger feeder is most commonly used as a means for filling fine powder having the above-mentioned properties. FIG. 1 schematically shows the structure of an auger feeder. The powder in the hopper 2 is discharged from below the funnel 3 by rotating the screw-shaped auger 1. The lower part of the funnel is equipped with a resistor plate called a chrysanthemum 4 and a shutter to prevent flashing when the rotation of the screw is stopped and to provide quantitativeness. Such devices are most widely used for filling toner used in electrostatic copiers. However, the filling device using an auger feeder as shown in FIG. 1 has a drawback that high-speed filling is difficult when the container has a small opening. That is, the filling speed improvement using the auger feeder can be realized by either increasing the auger diameter or increasing the auger rotation speed, but if the container mouth is small, the auger diameter cannot be increased, Further, increasing the auger rotation speed has the problems that the fine particles are crushed to reduce the average particle size, or heat is generated to adversely affect the fine powder. In order to solve this, the auger diameter can be increased by adopting a structure in which the funnel 6 is provided under the auger feeder 5 and the container 7 is placed under the funnel 6 as shown in FIG. However, for example, a toner used in an electrostatic copying machine, especially a non-magnetic two-component toner, has a large bridging property, and it takes a considerable time to drop the toner discharged from the auger feeder into a container, or The current situation is that it will not fall unless a large amount of vibration is added. Therefore, for example, a rotary filling method is adopted in which an empty container introduced from the left as shown in FIG. 3 which is used for filling powder at high speed is filled in the rotary unit and flows out to the right after the filling is completed. It was very difficult.

The present invention has been made in view of the above circumstances, and is used for charging the fine powder discharged from the filling device to the funnel at a high speed into the container at a high speed, particularly for an electrostatic copying machine. It is an object of the present invention to provide a powder filling method suitable for application to toner filling.

[0005]

In order to achieve the above object, the present invention introduces gas into a filling device to supply fine powder having improved fluidity to increase the dropping speed from the funnel to the container. The powder filling method is characterized in that Compared with the known methods, such a filling method increases the filling speed. It does not require a complicated system. It can be downsized and made compact, and it has remarkable advantages in reducing the cost of the filling device. There is.

DETAILED DESCRIPTION OF THE INVENTION The present invention is described in detail below.
FIG. 4 shows a schematic diagram of an embodiment of the present invention. The filling device 9 is composed of a hopper 10 and an introduction portion 12 connected to the lower end thereof, and an air suction port 11 is provided on the side surface of the hopper 10. The filling device 9 can aerate the fine powder to improve the fluidity and fill it. That is, the fine powder contained in the filling hopper 10 is fluidized by supplying air from the air suction port 11. The air suction port 11 is provided on the side surface of the hopper 10, and it is desirable to have two or more locations in order to uniformly promote fluidization. For example, it is provided in the middle and lower parts of the hopper, or on the circumference of the side surface for multiple objects. It is preferable to provide such a structure. Also, the shape of the suction port can be arbitrarily devised,
It is preferable to have a mesh shape for uniform aeration. The air sucked from the air suction port may be intermittent, but is preferably continuous. The air inflow amount can be arbitrarily set depending on the hopper diameter and the powder amount, but preferably 100 Nl / hr or more and 5000 N or more.
If it is 1 / hr or less, the powder can be appropriately fluidized. In addition, it is also preferable to provide a screw 18 or the like at a portion of the hopper 1 that is connected to the introduction portion 12 to promote the movement of the powder.

The fluidized fine powder is supplied to the funnel portion 13 at high speed through the introduction portion 12. As the introduction part of the present invention, for example, a single screw pump is used. In the uniaxial screw pump, a male screw type rotor 15 (cross section having a perfect circle) is installed in a female screw type stator 16 (cross section having an oval shape). When the rotor 15 is rotated at an eccentric shaft center, the rotor 15 is It is a volumetric pump having a mechanism that performs vertical movement while rotating inside the stator 16 and continuously sends out a filling object filling a space volume formed between the rotor and the stator from the suction side to the discharge side. By using this uniaxial screw pump, the powder to be filled can be quantitatively continuously supplied to the funnel part at high speed without flushing. An example of a device using this single-shaft screw pump as an introduction part is a mono pump manufactured by Hyōjin Kikai Co., Ltd. The volume of the funnel portion 13 is preferably 50% or more of the volume of the container 17. Further, it is desirable that the funnel angle θ is small so that the powder easily flows into the container 17, and for example, it is preferably 20 ° or more and 90 ° or less. Since the fine powder filled in the funnel portion 13 at a high speed is fluidized, the container 1 is swiftly charged by its own weight.
Move to 7. The seal portion 14 seals the funnel 13 and the container 17, and has the meaning of preventing dust and loss of raw materials.

Further, in the present invention, it is also preferable to provide a mechanism for feeding gas to the funnel portion 13 so as to further fluidize the fine powder.
Should be provided. The following is an experimental example comparing the filling method according to the present invention with a known filling method.

[0009]

【Example】

Experimental Example A 1200 cc synthetic resin funnel was attached to a 1000 cc toner container, and a non-magnetic two-component toner having a volume average particle size of 10 μm and a true specific gravity of 1.0 was used as shown in FIG. 250 g of the toner was filled with a filling time of 1.5 SEC while introducing air using a mold. The time required for the toner to move from the funnel to the container was 10 SEC, and the apparent density of the toner at that time was 0.25.

Comparative Example A similar experiment was conducted by replacing the mono pump of the experimental example with an auger feeder. Then, the toner was bridging in the funnel, and the toner could not be filled in the container in the stationary state. When the funnel and container are vibrated, 60 SE
At about C, it moved from the funnel to the container. The apparent density of the toner immediately after being discharged from the auger feeder is 0.40.
Met.

[0011]

As described above, by using the filling method according to the present invention, it becomes possible to fill the toner fine powder at a filling speed which is about 6 times faster than the conventional one, and it is not necessary to apply vibration. There is no concern about noise, dust, etc., and the system is simple, which has a remarkable effect on cost reduction of fine powder filling. Further, by combining the present invention with a rotary filling method, it is possible to realize a filling speed which has not been conceived until now.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a conventional auger feeder.

FIG. 2 is a conventional filling method in which a funnel is provided under the auger feeder and a container is placed under the funnel.

FIG. 3 is a schematic representation of a rotary filling machine.

FIG. 4 is an example of a schematic configuration of a powder filling device according to the present invention.

[Explanation of symbols]

 1 Auger Screw 2 Hopper 3 Auger Funnel 4 Kikuza 5 Auger Feeder Filling Machine 6 Funnel 7 Filled Container 8 Filling Machine 9 Filling Device 10 Hopper 11 Air Suction Port 12 Introducing Port (Single Screw Pump) 13 Rotor 14 Sealing Part 15 Rotor 16 Stator 17 Filled Container 18 Screw 19 Air Inlet

Claims (4)

[Claims] 1. A toner filling method characterized in that the toner is supplied to a filling device provided with a hopper and an introduction part connected to the lower end thereof, and gas is introduced into the hopper part in the filling device. 2. The toner filling method according to claim 1, wherein the introducing portion is a uniaxial screw pump. 3. The toner filling method according to claim 1, wherein the powder discharged from the lower end opening of the filling device is supplied to a funnel provided below the filling funnel, and the container to be filled is filled from the funnel. . 4. The toner filling method according to claim 3, wherein gas is introduced into the funnel.