JP2003311623A - Grinding meterial-mixing tank of blast device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a grinding material-mixing tank of a pressure blast device where grinding material does not aggregate inside the tank and ratholes are not formed even when grain size of powder of the grinding material becomes small and the grinding material can be smoothly and stably injected, when gas and the grinding material are mixed and fed using the grinding material- mixing tank. <P>SOLUTION: The grinding material-mixing tank 1 comprises, in a pressurizably formed tank body 2, a grinding material-feeding pipe 4 that has a grinding material-introducing port 3 opening inside the tank body 2 and penetrates through the tank body 2, and an annular gas-supply pipe 5 that has many gas releasing holes 52 in an annular pipe body 51 and can release pressurized gas into the tank body 2. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blasting device used for surface processing in a wide range of industrial materials such as electronic materials and organic materials, and more particularly, a stable injection is performed by using fine powder as an abrasive. The present invention relates to a pressure-type sandblasting device that is capable of performing high-precision machining and has high blasting power.

[0002]

2. Description of the Related Art Conventionally, a sandblasting apparatus is known in which powder such as an abrasive is mixed with a gas such as compressed air and jetted at a high speed from the tip of a nozzle. The sandblasting device is used to spray a mixture of powder and gas sprayed from the tip of a nozzle onto the surface of a workpiece to perform various processes such as polishing, grinding or deburring of the workpiece. There is.

In the sandblasting apparatus, a pressure type in which an abrasive material and pressurized air are mixed and injected in a pressure vessel, and a negative pressure generated when air is injected from a nozzle tip sucks and mixes the abrasive material. There is a suction type in which an abrasive is jetted by using a nozzle device formed as described above. Among them, the pressure type blasting device, compared with the suction type device,
There is an advantage that the power when blasting is large.

FIG. 6 shows the structure of a mixing tank of a conventional pressure blast device. The conventional mixing tank, as shown in the same figure, as the mixing tank 100, a tank main body 102 having a space for holding the abrasive 101 inside and formed to be pressurizable,
Abrasive delivery pipe 1 provided with an abrasive introduction port 103 penetrating the inside of the tank body 102 and opening to the inside of the tank
04, and a pressure pipe 105 for pressurizing the inside of the tank. A compressor or the like is connected to the inlet side 104a of the abrasive material delivery pipe and the pressurizing pipe 105 so that compressed air can be delivered. Abrasive delivery pipe
The outlet side 104b of 104 is connected to the injection nozzle.

In order to inject the abrasive using the mixing tank shown in FIG. 6, after putting the abrasive 101 in the tank main body 102,
The container is closed, and compressed air from the compressor is sent from the pressure pipe 105 and the inlet side 104a of the abrasive feed pipe 104.
Since the compressed air that has entered from the pressurizing pipe 105 pressurizes the inside of the tank body, the abrasive 101 is the abrasive inlet of the abrasive delivery pipe 104.
Sent to 103. Abrasive feed pipe 104 from abrasive inlet 103
The abrasive material 101 sent inside is the inlet side 104a of the abrasive material delivery pipe.
Compressed air introduced from the outlet side of the abrasive material delivery pipe
It is pressure-fed to 104b and ejected from the tip of the ejection nozzle connected to the outlet side of the abrasive material delivery pipe.

In the conventional pressure type sandblasting apparatus,
Only the abrasive particles having an average particle diameter of 1.4 mm to 0.3 mm were applicable. In recent years, various manufacturing and processing industries have demanded that a blasting device be used for polishing a fine surface pattern. Further, the fine surface pattern is always required to be further miniaturized. As the surface pattern is finely ground, the abrasive must be a fine powder having a small particle size.

[0007]

However, when the particles of the abrasive become small and become a fine powder, when the inside of the mixing tank is pressurized by compressed air, the fine abrasive powder aggregates due to the pressure. However, the bulk density becomes large, the fluidity is lost, and the material cannot be fed to the abrasive feed pipe 104. As a result, at the beginning of operating the blasting device, the mixture of the abrasive and air is injected from the tip of the injection nozzle, but with the passage of time, the powder of the abrasive loses fluidity due to the pressure in the tank, The amount of the abrasive material sent out to the abrasive material delivery pipe becomes small, and the injection amount becomes small. in this way,
In the present invention, a state in which the bulk density of the abrasive powder is increased and the fluidity is lost is referred to as "aggregation".

Since the agglomerate of the abrasive in the mixing tank progresses, when air is sent from the filter 107 into the mixing tank, a passage is formed between the pressurizing port and the abrasive introducing port of the abrasive delivering pipe to allow only air to flow. As a result, no abrasive is jetted from the tip of the jet nozzle, and only air is jetted. In this way, the agglomerates of the inside of the tank are aggregated, and the air passage formed as a void communicating with the layer of the agglomerates from the air inlet to the outlet of the mixing tank is referred to as a "rat hole" in the present invention. say.

In the conventional pressurizing type blasting apparatus, it has been impossible to prevent the agglomeration of the abrasive powder particles inside the mixing tank when the abrasive particles become fine. Therefore, a pressure blast device using powder having a small particle size as an abrasive is not practical. Incidentally, a suction type blasting device, which is not a pressure type, is known as a device improved so as not to lose the fluidity of the abrasive powder.
(For example, JP-A No. 2-131871).

As described in the section of the prior art of Japanese Patent Laid-Open No. 2-131871, when the abrasive is not a fine powder, a ceramic filter 107 is provided on the bottom plate 106 of the mixing tank 102, A means for sending air into the tank through the filter 107 to prevent the abrasive 101 from aggregating inside the tank is known. The present inventors have tried to utilize this means in the mixing tank of the pressure blasting device.

However, as shown in FIG. 6, when jetting is carried out from the bottom of the mixing tank 100 while sending a small amount of air through the ceramic filter 106, the abrasive material decreases in a mortar shape inside the tank body, In the portion outside the dotted line P in FIG. 6, that is, in the portion close to the inner wall of the tank body, the abrasive loses fluidity and agglomerates, and simply blowing air from the bottom of the container causes the abrasive to spray. I can't do it anymore. Also, when jetting is performed while sending in a large amount of air from the bottom of the mixing tank, the abrasive 1
An air passage Q called a rat hole is formed up to the upper surface of 01, which also loses fluidity.

Further, Japanese Patent Laid-Open No. 2-131871 proposes a suction type blasting device in which a vibrating plate is attached to the bottom side space of a container to give vibration to an abrasive to prevent aggregation. However, installing a vibrating device such as a vibrating plate inside the mixing tank, which is a pressurizing container, has a problem in that the bulk density becomes high due to the influence of vibration, and the liquid loses fluidity and cannot be jetted.

The present invention has been made in view of the above-mentioned problems, and even when the particle size of the powder of the abrasive is reduced, when the gas and the abrasive are mixed and sent out, the abrasive is agglomerated inside the tank. It is an object of the present invention to provide an abrasive material mixing tank for a pressure blasting device capable of stably ejecting an abrasive material without forming a rat hole.

[0014]

The present invention provides (1) an abrasive mixing tank used in a blasting device using a pressurized gas, wherein the tank body is provided inside a tank body that is pressurizable. Abrasive delivery pipe that has an abrasive inlet that opens inside and penetrates the tank body, and a large number of gas discharge holes in an annular pipe body that provides pressurized gas inside the abrasive that is placed in the tank body. An abrasive gas mixing tank, which is provided with a releasable annular air supply pipe, (2) a tank for adjusting the internal pressure rise inside the tank main body due to the pressurized gas released from the annular air supply pipe The gist of the abrasive mixing tank according to (1) above, wherein the internal pressure adjusting pipe connects the tank body and the abrasive sending pipe outlet side pipe and is provided so that pressurized gas can be sent to the outside of the mixing tank. Is.

[0015]

1 is a schematic view showing an example of a blasting device. As shown in FIG. 1, the abrasive mixing tank 1 includes a tank main body 2 inside a tank main body 2 that is pressurizable.
The abrasive feed pipe 4 provided with the abrasive introduction port 3 opening to the inside of the tank so as to pass through in the horizontal direction is attached, and further a large number of gas discharge holes are provided in the annular pipe body and inserted into the tank body. An annular air supply pipe (5) capable of releasing pressurized gas is provided inside the abrasive material.

In FIG. 1, outside the tank body 2, a pressurized gas supply pipe 9A is connected to the inlet side of the abrasive material delivery pipe 4a, and a pipe 14 and an injection nozzle downstream thereof are connected to the outlet side 4b.
15 are connected. Similarly, a pressurized gas supply pipe 9B is connected to the annular air supply pipe 5. Further, in the tank main body 2, a tank internal pressure adjusting pipe 6 for adjusting the internal pressure of the pressurized gas sent from the annular air supply pipe 5, and a pressure relief used when returning the internal pressure of the tank main body 2 to normal pressure. Piping 7 is provided.

As shown in FIG. 1, the gas supply pipe 9A on the inlet side of the abrasive material delivery pipe 4 is a pressurized gas supply device 8A such as a compressor, a pressure control valve 10A for adjusting the pressure of the pressurized gas,
A solenoid valve 11A for controlling the supply of pressurized gas is attached. Also, the gas supply pipe 9B connected to the annular air supply pipe 5
A pressurized gas supply device 8B such as a compressor, a pressure control valve 10B for adjusting the pressure of the pressurized gas, and a solenoid valve 11B for controlling the supply of the pressurized gas are attached to the.

Further, the gas supply pipe 9A on the abrasive feed pipe 4 side
Is branched before the inlet side 4a of the abrasive feed pipe 4, one is connected to the abrasive feed pipe 4, and the other one is a bypass connected to the nozzle pipe 14 on the outlet side of the abrasive feed pipe. Piping
It is connected to 12. A flow rate adjusting valve 13 for adjusting the flow rate of the pressurized gas is attached to the bypass pipe 12.

FIG. 2 is a cross-sectional view showing a main part with a part of FIG. 1 omitted. As shown in FIG. 2, the tank body 2 is formed so that the inside of the tank can be sealed except for the abrasive introduction port 3 and the inlet of the tank internal pressure adjusting pipe 6. In the embodiment shown in FIG. 1, the tank main body 2 is composed of a cylindrical container 2a having an open upper surface and a lid 2b capable of sealing the opening of the container 2a, but it can hold an abrasive. The container is not limited to such a shape as long as it can be pressurized. The tank body 2 shown in FIG. 2 has a lid 2b after the lid 2b is opened and an abrasive is put therein.
Can be used in batch mode by closing and sealing.
Although not shown, a pipe for supplying the abrasive to the inside of the tank main body 2 is connected to the tank main body 2 above the tank main body 2, and the abrasive is transferred from a separate abrasive storage tank or the like. It may be configured so that it is sent to the inside of the tank body.

The shape of the tank body 2 is not limited as long as it can hold powder particles of an abrasive and has a closed structure capable of pressurizing, and that each of the above parts can be connected and connected.
In the embodiment shown in FIGS. 1 and 2, the tank body 2 is formed in a cylindrical shape, but the shape is not particularly limited to this.

The abrasive feed pipe 4 is provided at a portion near the bottom of the tank body so as to penetrate the inside of the tank body 2 in the horizontal direction. It is sufficient that the abrasive introduction port 3 communicates a mixture of the abrasive and the gas in the abrasive delivery pipe so that the mixture can be provided with a plurality of holes. In addition, the grinding material inlet 3
In the embodiment shown in the figure, is provided so as to be opened on the lower side of the abrasive feed pipe 4, but it is not particularly limited to this position.

The annular air supply pipe 5 is formed by providing a large number of gas discharge holes 52 in an annular pipe body 51 and connecting a pipe 53 for sending a pressurized gas to the pipe body 51. The pipe 53 is shown in FIG. It is connected to the pressurized gas supply device 8B shown in. Pipe body 51
Is a hollow body through which a pressurized gas can pass, and the outer shape may be formed in a ring with a lack of a central portion (so-called donut shape), may be a circular ring, or may be a ring other than a circle. .

The size and number of the gas discharge holes 52 are not particularly limited, but it is preferable that the gas discharge holes 52 are provided so as to be distributed over the entire annular pipe body 51. The gas discharge hole 52 is an annular pipe body 51.
Above, in the horizontal direction (center or side direction of the tank body), downward, diagonally upward, diagonally downward, or any combination of two or more of these directions. As described above, the pipe body 51 can be provided at an appropriate position.

The position where the gas discharge hole 52 is provided is particularly preferably a position where the gas is discharged toward the center side in the horizontal direction of the annular body, or upward or downward, and the rat hole of the abrasive material inside the tank body. Especially excellent in prevention effect.

In the embodiment shown in FIGS. 1 and 2, the annular air supply pipe 5 is installed so that the annular body is horizontal inside the tank body. However, the annular air supply pipe 5 is not limited to such an embodiment, and the annular air supply pipe 5 is not limited thereto. It may be mounted at an angle so that it has an angle to the horizontal. The position where the annular air supply pipe 5 is provided is the gas discharge hole 52 of the pipe body 51 in the vertical direction of the tank body 2.
Is preferably provided above the abrasive inlet 3 of the abrasive delivery pipe.

Abrasive material 16 held inside the tank body 2
Is sent from the abrasive material inlet 3 into the abrasive material delivery pipe 4 by the pressure of the pressurized gas released from the annular air supply pipe 5. The mixture of the pressurized gas and the abrasive is supplied from the gas supply pipe 9A shown in FIG. 1 on the inlet side of the abrasive delivery pipe 4 by the pressurized gas from the delivery pipe outlet side outside the tank of the abrasive delivery pipe 4. Nozzle piping 1 delivered to the nozzle piping 14 shown in FIG.
It is ejected to the outside from an injection nozzle 15 provided at the tip of 4.

The tank internal pressure adjusting pipe 6 shown in FIG. 1 is provided with the tank main body 2 by the pressurized gas sent from the annular air supply pipe 5.
It is provided to adjust that the internal pressure rises too much, and is adjusted to an appropriate internal pressure so that the pressure inside the tank body 2 does not become too high, preventing the abrasive from aggregating again, The injection can be further stabilized.

The tank internal pressure adjusting pipe 6 shown in FIG. 2 is designed so that the abrasive 16 inside the tank body 2 does not flow out of the pipe 6.
The abrasive material delivery pipe outlet side pipe 14 shown in FIG. 1 can be provided so that the pressurized gas is delivered. Preferably, the opening 6a of the tank internal pressure adjusting pipe 6 is opened inside the tank body 2.
However, it is preferably provided so as to be located above the tank body 2, and more preferably, the opening 6a is provided in the lid body 2a which is the ceiling surface of the tank body 2. This is because when the opening of the tank internal pressure adjusting pipe is provided on the side surface of the tank body, the abrasive is less likely to aggregate on the inner surface of the tank body near the opening, but the abrasive is less likely to aggregate on the inner surface of the tank body far from the opening. This is because there is a risk of aggregation.

The size of the opening 6a of the tank internal pressure adjusting pipe 6, the inner diameter of the pipe 6b, etc. can be appropriately changed according to the size of the injection nozzle.

FIG. 3 is a schematic view showing another example of the abrasive mixing tank of the present invention. As shown in FIG. 3, inside the tank body 2 of the abrasive mixing tank, there is an umbrella-shaped member 18 having an inclined surface 17 that becomes lower in the lateral direction from the center of the tank body 2.
Is preferably provided. The umbrella-shaped member 18 is composed of an inclined surface 17 and a fixing member 19 for supporting the inclined surface and fixing it inside the tank body. As shown in FIG. 3, the umbrella-shaped member 1
8 is preferably provided so that the inclined surface 17 is located at a position lower than the pipe body 51 of the annular air supply pipe 5.

Examples of the abrasive material 16 to be put in the abrasive material mixing tank include natural silica sand, alumina and silicon carbide powder, glass beads, fine steel balls, ceramic beads and the like. Air is usually used as the pressurized gas, but a gas such as nitrogen can also be used. The abrasive mixture tank of the present invention has a particle size of 1.4 mm to 1 as an abrasive.
It can be used in the range of 0 μm. In particular, it is possible to use abrasive particles having a particle size of 300 μm or less, which is difficult with the conventional pressure blasting device.

[0032]

[Example] Alumina having an average particle diameter of 20 μm was used as abrasive particles, and the shape of the cylinder was as shown in FIG. The shape shown in Fig. 2 is used by using the mixing tank in which the specified abrasive material delivery pipe with a diameter of 38 mm and inner diameter of 14 mm is installed at a height of 100 mm from the inner bottom surface of the tank body (based on the center of the abrasive material delivery pipe). The annular air supply pipe of No. 2 was installed so as to be located above the abrasive delivery pipe in the abrasive layer, and the injection was performed under the following conditions. A graph showing the relationship between the tank weight and the time obtained as a result of the injection is shown in FIG. Also, FIG.
Fig. 5 shows a graph in which the tank weight reduction amount is converted into the injection amount. From this result, it can be seen that the injection amount is uniformly controlled. Injection pressure: 0.36MPa Pressure of annular air supply pipe: 0.4MPa Tank internal pressure: 0.32MPa Tank outlet pressure: 0.32MPa

[0033]

As described above, the present invention provides an abrasive material delivery pipe penetrating the tank body and an annular pipe body provided with an abrasive material inlet opening inside the tank body which is formed so as to be pressurizable. By adopting a configuration in which a large number of gas discharge holes are provided and an annular air supply pipe capable of discharging pressurized gas is provided inside the abrasive put in the tank body, the particle size of the abrasive powder Even if the size becomes small, a rat hole is not formed when the gas and the abrasive are mixed and sent out, and an abrasive mixture tank of the pressure blasting device that can stably perform the injection of the abrasive can be obtained. . The blasting device using this abrasive material mixing tank is capable of stably performing efficient machining with excellent machining accuracy when performing various processes.

Further, when a tank internal pressure adjusting pipe capable of sending gas inside the tank main body is provided by connecting the tank main body and the outlet pipe for the abrasive material sending pipe, the internal pressure in the tank main body can be adjusted appropriately, It is possible to reliably prevent the abrasive from aggregating due to the pressure of the pressurized gas delivered from the air delivery pipe, and perform stable injection.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an example of a device of the present invention.

FIG. 2 is a cross-sectional view of main parts of the device shown in FIG.

FIG. 3 is a schematic view showing another example of the device of the present invention.

FIG. 4 is a graph showing the relationship between tank weight and time when the abrasive is sprayed using the abrasive mix tank of the present invention.

5 is a graph in which the data of the tank weight in the graph shown in FIG. 4 is converted into an injection amount.

FIG. 6 is a cross-sectional view showing a conventional pressurizing type blasting machine abrasive mixing tank.

[Explanation of symbols]

1 Abrasive mixing tank 2 Tank body 3 Abrasive material inlet 4 Abrasive delivery pipe 5 Circular air supply pipe 51 annular pipe body 52 Gas release hole 53 Ring pipe piping 6 Tank internal pressure adjustment piping 8A, 8B pressurized gas supply device 9A, 9B gas supply piping

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Isao Niioka             1-37 Yanagibashi, Taito-ku, Tokyo Stock market             Inside the company nichu

Claims (2)

[Claims] 1. A grinding material mixing tank used in a blasting device using a pressurized gas, wherein a grinding material inlet opening to the inside of the tank body is provided inside a tank body that is pressurizable. An abrasive material delivery pipe penetrating the tank body, and an annular air supply pipe capable of releasing a pressurized gas inside the abrasive material provided in the tank body with a large number of gas emission holes provided in the annular pipe body are provided. Abrasive mixing tank. 2. A tank internal pressure adjusting pipe for adjusting an internal pressure increase in the tank main body due to a pressurized gas discharged from an annular air supply pipe connects the tank main body and an abrasive material delivery pipe outlet side pipe and pressurizes. 2. The abrasive mixing tank according to claim 1, which is provided so that the gas can be sent to the outside of the mixing tank.