JPS6236554Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for supplying powder to a jet nozzle from which the powder is ejected, for example in an electrostatic coating apparatus.

Generally, it is known that a light diffusing film is formed on the inner surface of the bulb of an incandescent light bulb by attaching powder such as silicon dioxide, but electrostatic Painting method is used. This method involves inserting nozzles that eject the powder into a valve, generating static electricity between these nozzles and the valve, and causing the powder ejected from the nozzle to adhere to the inner surface of the valve. By doing so, a light diffusing film is formed.

By the way, the above nozzle is connected to a tank containing powder from which the powder is sent out, but the conventional device for taking out powder from this tank is to attach an injector to the top lid of the tank. At the same time, a suction pipe extending toward the bottom of the tank is connected to this injector, and the powder in the tank is sucked up through this suction pipe.

However, according to such a structure, since the powder is sucked into the suction pipe in a deposited state, there is a drawback that the powder has poor fluidity because the individual powder remains clumped together. For this reason, there is a risk that the suction pipe or the suction system may be clogged with powder, or that the amount ejected to the valve may vary. Moreover, if the tank height is increased to increase the amount of powder accumulated,
The total length of the suction pipe also needs to be increased, which would cause the injector to have the problem of requiring a stronger suction force.

The present invention was developed based on these circumstances, and its purpose is to break up and disperse powder clumps during powder suction to prevent this powder from clogging in the middle of the suction system. As well as being able to
It is an object of the present invention to provide a powder supply device that reduces variation in the amount of powder ejected and improves reliability.

That is, in order to achieve the above purpose, the present invention
A suction port is provided on the side surface of the tank containing the powder, located above the top surface where the powder is stored, and an injector for sucking the powder in the tank is provided in the suction port, and the first injector The discharge end of the tank is opened toward the inside of the dispersion container installed at the top of the tank,
The powder in the tank is supplied to the dispersion container by the first injector and ejected into the dispersion container so that the powder is dispersed and suspended;
The dispersion container has its lower end open to the tank so that hardened powder and excess powder can be returned to the tank, and a suction port is provided at the top of the dispersion container. This is characterized by the provision of a second injector that sucks the powder floating within the dispersion container.

The present invention will be explained below based on an embodiment shown in the drawings.

In the figure, 1 is a base, and a storage tank 2 is mounted on this base 1. A top lid 3 is attached to the top opening of the tank 2 so as to be openable and closable, and a lid 4 for closing the bottom opening is attached to the bottom opening. A partition plate 5 is interposed between the lid body 4 and the storage tank 2, and the partition plate 5 is made of a porous material having air permeability.
Therefore, the bottom of the tank 2 has a double structure, thereby dividing the inside of the tank 2 into a powder storage chamber 6 and a pressure introduction chamber 7. In the powder storage chamber 6, a powder 8 having light-diffusing properties, such as silicon dioxide, is stored. Further, high pressure air is supplied to the pressure introduction chamber 7 via an air pipe and an air pump 10, and the high pressure air introduced into the pressure introduction chamber 7 passes through the partition plate 5 as shown by the arrow in the figure. The powder is ejected from the entire bottom surface of the powder storage chamber 6 into the powder storage chamber 6.

Incidentally, a plurality of suction ports 11 are provided on the circumferential surface of the bottom side of the tank 2 at intervals in parallel to the circumference. It is located at the bottom. A first injector 13 connected to the air pump 12 is attached to each suction port 11. Therefore, when high-pressure air is supplied to the first injector 13, the inside of the suction port 11 becomes negative. The powder 8 in the tank 2 is directly suctioned by the pressure. Further, an exhaust chamber 14 for releasing pressure inside the tank 2 is attached through the upper lid 3, and a number of dispersion containers 15 corresponding to the first injectors 13 are attached. Dispersion container 15...
The bottom surface is open and the powder storage chamber 6 of the tank 2
For this reason, each dispersion container 15...
The inside forms a dispersion chamber 16 that is continuous with the inside of the powder storage chamber 6. And on the top of each dispersion container 15...
A powder discharge hose 17 that communicates the inside of the dispersoid 16 with the discharge port of the first injector 13 is removably connected, so that the first injector 13 is connected inside the dispersion chamber 16. The powder 8 sucked by the pump is discharged together with high-pressure air. Further, suction ports 18 are provided on the upper surface of the dispersion container 15, and a second injector 20 connected to an air pump 19 is attached to each suction port 18. These second injectors 2
The jet nozzles 21 are connected to the discharge ports 0, and the jet nozzles 21 are covered with, for example, bulbs 22 for incandescent light bulbs. Therefore, the second
When high pressure air is supplied to the injector 20...,
The suction ports 18 become negative pressure and the powder 8 discharged into the dispersion chamber 16 is sucked, and this sucked powder 8
is ejected from the tips of the jet nozzles 21 toward the inner surface of the valve 22.

A vibrator 23 for vibrating the storage tank 2 is attached to the bottom of the base 1, and in conjunction with the supply of high-pressure air into the tank, the powder stored in the tank 2 is 8 is now given fluidity.

However, according to such a configuration, the suction port 11 is provided on the side surface of the tank 2, and the first injector 13 is attached to the suction port 11 so that the powder 8 in the tank 2 can be directly sucked from there. This eliminates the need for a conventional suction pipe, and eliminates problems such as the powder 8 clogging the pipe. Moreover, the powder 8 that is sent through the powder discharge hose 17 toward the dispersion chamber 16 above the tank is pushed out by the pressure of high-pressure air, so that the powder 8 is transferred to the powder discharge hose 17. There is no risk of clogging in 17. Powder discharge hose 17
Since the dispersion chamber 16 serves as a diffusion space, the powder discharged into the dispersion chamber 16 via...
It diffuses and floats within 6. And this dispersion chamber 1
Since the lower end of the dispersion chamber 6 is open to the powder storage chamber 6 in the tank 2, a part of the powder discharged into the dispersion chamber 16 falls into the tank 2 by gravity.
Particularly large particles of powder or compacted powder are returned to tank 2, and finer, lighter powder is suspended in dispersion chamber 6.

The second injector 20 absorbs the powder suspended in the dispersion chamber 6 and sends it to the jet nozzle 21.
Since the particles of the suspended powder are fine and light, no clogging occurs in the second injector 20 or the jet nozzle 21. Therefore, the suction of the powder 8 is performed smoothly, and fluctuations in the suction amount of the second injector 20 are reduced. Therefore, a certain amount of powder 8 is always ejected from the fume nozzle 21 toward the inner surface of the bulb 22, and the thickness of the light diffusing film formed on the inner surface of the bulb 22 becomes uniform. This has the advantage of improving quality.

Further, the work of supplying the powder 8 into the tank 2 and the maintenance and inspection work inside the tank 2 are performed by removing the top cover 3, but a long pipe is attached to the top cover 3 as in the past. If this happens, it is necessary to lift the top cover 3 beyond the length of the pipe, which impairs work efficiency. However, according to the above configuration, since the upper lid 3 is not provided with any member that protrudes into the tank 2, there is no need to lift the upper lid 3 high when removing the upper lid 3. Therefore, the upper lid 3 can be easily attached and detached by removing the powder discharge hose 17 from the dispersion container 15, improving work efficiency.

Note that the powder supply device according to the present invention is not limited to supplying powder to a jet nozzle of an electrostatic coating device, and can of course be used in various other fields.

As detailed above, according to the present invention, the powder sucked in by the first injector is discharged into the dispersion container and once diffused and separated, and the powder floating in the dispersion container is transferred to the second injector. Since the powder is sucked through the suction system, there is no clogging in the powder suction system, and since the powder is supplied with an even grain size, there is less variation in the amount of injection, resulting in a stable supply. It has excellent effects such as being able to perform

[Brief explanation of the drawing]

The drawing is a sectional view showing an embodiment of the present invention. 2...Storage tank, 6...Powder storage chamber, 8...
Powder, 11... Suction port, 13... First injector, 15... Dispersion container, 16... Dispersion chamber, 17...
...Powder discharge hose, 18...Suction port, 20...Second injector, 21...Blow nozzle.

Claims (1)

[Scope of utility model registration request] A suction port is provided on the side surface of the tank containing the powder, located below the top surface of the storage of the powder, and a first injector for sucking the powder in the tank is provided in the suction port. The discharge end of the injector No. 1 is opened toward the inside of the dispersion container installed at the top of the tank, and the dispersion container opens its lower end to the tank and has a suction port at the top. 1. A powder supply device characterized in that a second injector is provided for sucking powder floating therein.