JPS6218305Y2 - - Google Patents

Description

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

Generally, it goes without saying that a light diffusing film is formed on the inner surface of the bulb of a white 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 the valve, generating static electricity between these nozzles and the valve, and causing the powder ejected from the nozzles to adhere to the inner surface of the valve. By doing so, a light diffusing film is obtained.

By the way, the above nozzle is connected to a tank containing powder, but when taking out the powder in this tank via an injector, if the fluidity of the powder in the tank is poor, a certain amount of It becomes difficult to suction the powder smoothly, and there is a risk that the amount of powder taken out may fluctuate from moment to moment. If this happens, the amount of powder ejected to the inner surface of the bulb becomes non-uniform, resulting in problems such as variations in the thickness of the light diffusing film.

The present invention was developed based on these circumstances, and its purpose is to create a powder supply device that improves the fluidity of powder in a tank and can always take out a fixed amount of powder. This is what we are trying to provide.

That is, in order to achieve the above purpose, the present invention
A rotating blade is provided at the bottom of the tank, and the rotating blade stirs the powder at the bottom of the tank, and high-pressure air is blown onto the agitated powder.

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

1 in the figure is a storage tank, and this storage tank 1
The top opening is closed by a top lid 2, and a lid 3 is attached to the bottom opening to close this. A breathable partition plate 4 made of a porous material is interposed between the lid body 3 and the storage tank 2. The partition plate 4 allows the bottom of the tank 1 to have a double bottom. Structurally, the inside of the tank 1 is divided into a powder storage chamber 5 and a pressure introduction chamber 6. In the powder storage chamber 5, a powder 7 having light-diffusing properties, such as silicon dioxide, is accumulated. On the other hand, a first injector 9 connected to an air pump 8 is attached to the upper lid 2.
A suction pipe 10 is led from the first injector 9, passing through the upper lid 2 and facing into the powder storage chamber 5. The tip of this suction pipe 10 is
It is embedded in the powder 7 and reaches the bottom of the tank near the partition plate 4. Therefore, when high-pressure air is supplied to the first injector 9, the inside of this suction pipe 10 becomes negative pressure and the powder is 7 is now being sucked up. Further, a dispersion container 11 whose lower surface is open is attached through the upper lid 2, and the inside of this container 11 constitutes a dispersion chamber 12 communicating with the inside of the powder storage chamber 5. The inside of this dispersion chamber 12 is communicated with the discharge port of the first injector 9 through a connecting pipe 13, so that the inside of the dispersion chamber 12 is filled with water sucked up by the first injector 9 and the suction pipe 10. Powder 7 is discharged together with high pressure air. and dispersion container 1
A suction port 15 is provided on the top surface of the air pump 1, and a second air pump connected to the air pump 8 is connected to the air pump 8.
An injector 14 is attached. A jet nozzle 16 is connected to the discharge port of the second injector 14, and the jet nozzle 16 is covered with a bulb 17 for, for example, an incandescent light bulb. Therefore, when high-pressure air is supplied to the second injector 14, the inside of the suction port 15 becomes negative pressure, and the powder 7 discharged into the dispersion chamber 12 is sucked. The air is ejected from the tip of the jet nozzle 16 toward the inner surface of the valve 17 .

By the way, a motor 18 as a drive source is attached to the bottom outer surface of the lid 3, and a drive shaft 19 of this motor 18 is connected to the lid 3 and the partition plate 4.
It coaxially penetrates through and is led to the bottom of the powder storage chamber 5. At the leading-out end of this drive shaft 19,
An impeller 21 having a plurality of stirring blades 20 . The powder 7 is stirred.

Further, an air pump 23 is connected to the pressure introduction chamber 6 via a ventilation pipe 22, and this air pump 23 is operated in synchronization with the rotation of the impeller 21 to supply high pressure air into the pressure introduction chamber 6. It's becoming like that. The high-pressure air introduced into the pressure introduction chamber 6 passes through the partition plate 4 as shown by the arrow in the figure, and blows out from the entire bottom surface of the powder storage chamber 5 into the powder storage chamber 5. As a result, the powder 7 on the bottom side of the powder storage chamber 5 is blown upward.

It should be noted that an exhaust pipe 24 is attached through the upper lid 2 to relieve the pressure inside the powder storage chamber 5.

However, according to such a configuration, an impeller 21 is provided at the bottom of the storage tank 1 to agitate the powder 7 on the tank bottom side, and to blow high pressure air onto the powder 7 being stirred. So,
The fluidity of the powder 7 in the tank 1 is significantly improved. That is, if only the impeller 21 is provided at the bottom of the tank 1, the rotation of the stirring blades 20 in one direction may cause the powder 7 to be compressed in the opposite direction. When the wheel 21 is eliminated and the powder 7 is made to flow only by high-pressure air jetted from the bottom of the tank 1, a specific part of the accumulated powder 7 is penetrated through the accumulated powder 7. Therefore, it is unlikely that the powder 7 will be given fluidity.

However, according to the above configuration, the stirring blade 20...
As the powder 7 stirred by... is further exposed to high pressure air and diffused, the fluidization of the powder 7 in the tank 1 is promoted and the powder 7 is no longer compacted. Blocking is reliably prevented.

Therefore, clogging of the suction pipe 40, the first injector 9, etc. is prevented, and the powder 7
suction is performed smoothly, and fluctuations in the amount of suction are reduced. Therefore, since a fixed amount of powder 7 is always ejected from the fume nozzle 16 toward the inner surface of the bulb 17, the thickness of the light diffusion film formed on the inner surface of the bulb 17 becomes uniform, which has the advantage of improving quality. be.

In the above embodiment, a pressure introduction chamber was provided below the bottom of the powder storage chamber from which high-pressure air was blown up into the powder storage chamber. The piping may be directly connected, or the piping may be connected to the bottom side of the tank peripheral wall, and high pressure air may be blown out from there into the tank.

Further, 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.

The present invention described in detail above is for taking out powder stored in a tank through an injector.
A rotating blade is provided at the bottom of the tank, and the rotating blade stirs the powder at the bottom of the tank, and high-pressure air is blown onto the agitated powder. According to this, the powder stirred by the rotating blades is further exposed to high-pressure air and dispersed finely, which further promotes the fluidization of the powder in the tank and prevents the powder from becoming blocks. Definitely blocked. Therefore, clogging of the suction system such as the injector is prevented, and powder suction can be performed smoothly. Variations in the amount of powder supplied are greatly reduced, and stable supply can be achieved. play.

[Brief explanation of the drawing]

The drawing is a sectional view showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Storage tank, 7... Powder, 9... Injector (first injector), 21... Rotating blade (impeller), 4... Air permeable partition plate, 6... Pressure introduction chamber, 23... …air pump.

Claims (1)

[Scope of utility model registration request] In a powder supply device that takes out powder stored in a tank via an injector, a rotary blade is provided at the bottom of the tank to stir the powder on the bottom side of the tank, and a rotating blade is provided at the bottom of the tank to stir the powder at the bottom of the tank. A powder supply device comprising a high-pressure air supply mechanism that blows high-pressure air toward the agitated powder.