JP7353692B1 - Gas mixing device and electrical discharge treatment device using the gas mixing device - Google Patents

Abstract

An object of the present invention is to provide a compact gas mixing device that can uniformly and accurately generate a mixed gas consisting of multiple types of gases. [Solution] A multiplex structure in which pipes 1 to 3, each having a different diameter and the number of which is greater than the number of gas types to be mixed, are arranged in multiple layers, and communication with other pipes is cut off at the end, and each pipe 1 A plurality of gas ejection holes 8, 9, 10 formed on the side surfaces of ~3, gas supply ports 6 provided in pipes 1, 2 other than the outermost pipe 3 for supplying gas to be mixed, 7, each of the gas ejection holes 9 and 10 in the pipes 2 and 3 other than the innermost pipe 1 is formed in the pipe 1 and 2 that is one innermost of the pipes 2 and 3 in which the gas ejection hole is formed. The mixed gas of gas Ga and Gb, which is formed at a position other than the extension line of the gas ejection direction in the gas ejection holes 8 and 9, and which is supplied from the gas supply ports 6 and 7, is uniform in the inner space of the outermost pipe 3. The structure is such that the gas is ejected from the gas ejection hole 10 to the outside. [Selection diagram] Figure 1

Description

The present invention relates to a gas mixing device that mixes multiple types of gases, and a discharge treatment device using the same.

In discharge treatment equipment for surface modification, charging, or neutralization of resin materials, the strength and stability of discharge greatly affect the treatment quality. The discharge status can be evaluated by measuring the discharge current value, but it is known that the type and concentration of atmospheric gas in the discharge space where the discharge is generated affects the magnitude and stability of the discharge current value. For example, if the oxygen concentration in the air in the discharge space is high, the discharge current value will decrease. Therefore, nitrogen gas has been supplied to the discharge space under the atmosphere, and the oxygen concentration in the discharge space mixed with the nitrogen gas has been adjusted to a desired value.

Patent No. 6792786

As mentioned above, in order to stably maintain the desired discharge state, it is necessary to supply a constant amount of gas to the discharge space.
However, when different types of gases are directly supplied toward the discharge space to generate a desired mixed gas on the spot, it is difficult to make the mixed state in the space uniform.
On the other hand, there was also a gas mixing device for supplying a mixed gas with a pre-adjusted concentration, but this required a space for uniform mixing and a means to transport the mixed gas while maintaining the mixed state. There were problems in that the gas mixing and stirring space became large and the shape of the gas mixing and stirring space became complicated.
An object of the present invention is to provide a compact gas mixing device that can uniformly and accurately generate a mixed gas consisting of multiple types of gases.

The first invention is a gas mixing device for mixing multiple types of gases, in which pipes each having a different diameter and the number of which is greater than the number of gas types to be mixed are arranged in multiple layers, and the pipes are arranged at ends. a multilayer structure in which communication with other pipes is cut off, a plurality of gas ejection holes formed on the side surfaces of each of the pipes, and a plurality of pipes other than the outermost pipe constituting the outermost layer of the plurality of pipes ; a gas supply port provided in a pipe for respectively supplying each of the plurality of types of gases to be mixed, and supplying each of the plurality of types of gases to be mixed to the pipe, the innermost layer of the plurality of pipes; Each of the above-mentioned gas ejection holes in the pipes other than the innermost pipe constituting the gas ejection hole is located outside the extension line of the gas ejection direction of the gas ejection hole formed in the pipe one innermost of the pipe in which the gas ejection hole is formed. A mixed gas of gases formed at the position and supplied from the gas supply port is made uniform in the inner space of the outermost pipe, and is ejected to the outside from the gas ejection hole of the outermost pipe.

In a second aspect of the invention, the number of pipes forming the multiplex structure is one more than the number of gases to be mixed.

In a third aspect of the invention, the total opening area of each pipe in which the gas ejection holes are formed is set such that the total opening area of the outermost pipe is maximum.

In a fourth aspect of the invention, the gas ejection holes are formed on the side surface of each pipe in a linear area along the length of the pipe, and the gas ejection holes are formed between diametrically adjacent pipes. The linear areas are provided at positions 180° out of phase with each other in the circumferential direction of the pipe.

A discharge treatment apparatus according to a fifth aspect of the invention includes the gas mixing apparatus according to claim 1 or 2 provided in a processing chamber equipped with a discharge electrode to which a high voltage is applied, and the gas mixture ejected from the gas mixing apparatus. Gas is ejected into the discharge space near the discharge electrode.

According to the first invention, the gas supplied to the pipe is repeatedly ejected from the gas ejection hole of the pipe into the outer pipe, and then into the outer pipe, and reaches the outermost pipe. A uniform mixed gas can be ejected to the outside from the gas ejection hole of the outermost pipe.

In particular, since the positions of the gas nozzles formed in diametrically adjacent pipes are not lined up on the extension line of the gas ejection direction, the gas flow ejected from the gas nozzles of the inner pipe continues as it is to the outside. The gas will not pass through the gas outlet of the pipe, and will be stirred inside the pipe on the outside.
Further, since the number of pipes forming the multiplex structure is greater than the number of gases to be mixed, new gas is not supplied to pipes other than those to which gas is supplied. Therefore, gas is stirred in the pipe to which no gas is supplied, and the uniformity of the mixed gas is further promoted.
Furthermore, since gas supply and mixing can be realized using multiple pipes, the device can be made more compact.

According to the second invention, since the number of pipes is one more than the number of gases to be mixed, it is possible to prevent the device from becoming larger while achieving uniformity of the gases.

According to the third invention, the amount of gas in the pipe increases in the process from the innermost pipe to the outermost pipe, but since the opening area of the gas ejection hole in the outermost pipe is increased, the amount of gas to the outside is increased. Enables smooth mixed gas blowout.

According to the fourth invention, it is sufficient to form gas ejection holes in a fixed direction in each pipe, which facilitates the manufacturing thereof. Furthermore, the positions of gas ejection holes formed in diametrically adjacent pipes are in areas that are 180 degrees out of phase in the circumferential direction, maintaining the farthest positional relationship. Therefore, the gas ejected from the gas nozzle of the inner pipe does not directly reach the gas nozzle of the outer pipe, and passes through a long flow path before reaching the outer gas nozzle, so that the gas is mixed. Gases are easily mixed uniformly.

According to the fifth invention, by supplying the target mixed gas that has been homogenized with precision to the discharge space, uniform processing can be performed by stable discharge.

FIG. 1 is an axial cross-sectional view of the first embodiment. FIG. 2 is an enlarged diametrical cross-sectional view of the first embodiment. FIG. 3 is an enlarged diametrical cross-sectional view of the second embodiment. FIG. 4 is a schematic configuration diagram of the third embodiment.

[First embodiment]
A gas mixing device according to a first embodiment of the present invention will be explained using FIGS. 1 and 2. FIG. 1 is an axial sectional view of a pipe constituting the device, and FIG. 2 is a diametrical sectional view of the pipe.
The gas mixing device A of the first embodiment is designed to mix two types of gas, and as shown in FIGS. It has a multiple structure in which the axes of three pipes 1, 2, and 3 are aligned.

A second pipe 2 is provided between the first pipe 1, which is the innermost pipe constituting the innermost layer with the smallest diameter, and the third pipe 3, which is the outermost pipe with the largest diameter and constituting the outermost layer. , the intervals between the pipes are approximately equal, and the capacity of each pipe increases as it goes outward in the diametrical direction.
One end sides of the first to third pipes 1 to 3 are respectively closed with caps 1a, 2a, and 3a.

Further, the other end sides of the second and third pipes 2 and 3 are respectively closed with caps 2b and 3b that penetrate the first and second pipes 1 and 2.
In this way, the first to third pipes 1 to 3 are disconnected from other pipes at both ends thereof.

Further, the other end of the first pipe 1 is provided with a gas supply port 6 for supplying the first gas Ga, and the other end side surface of the second pipe 2 is provided with a gas supply port 6 for supplying the second gas Gb. A gas supply port 7 is provided for this purpose. Each gas supply source (not shown) is connected to these gas supply ports 6 and 7, respectively, so that the first and second gases Ga and Gb are supplied.
Note that the supply flow rate of the second gas Gb supplied to the outer second pipe 2 having a larger capacity among the first and second pipes 1 and 2 is set to be larger than the supply flow rate of the first gas Ga. There is.

Further, on the side surfaces of the first, second and third pipes 1, 2 and 3, a plurality of gas ejection holes 8, 9 and 10 are formed in a line in the length direction of the pipes, respectively.
As shown in FIGS. 1 and 2, these gas ejection holes 8, 9, and 10 are provided at positions that are 180 degrees out of phase with each other in the circumferential direction of the pipes 1, 2, and 3.

Further, the number of the gas ejection holes 8, 9, 10 formed in a line in each pipe 1, 2, 3 is equal, but the opening area of each gas ejection hole is in the order of the gas ejection holes 8, 9, 10. I'm trying to get bigger.
Therefore, the total opening area of each of the gas ejection holes 8, 9, and 10 is set to increase in the order from the first pipe 1, which is the innermost pipe, to the third pipe 3, which is the outermost pipe.

[Action/effect, etc.]
In the gas mixing device of the first embodiment, two types of gases Ga and Gb are mixed by supplying the first gas Ga from the gas supply port 6 and supplying the second gas Gb from the gas supply port 7. Can produce gas.
The first gas Ga supplied to the first pipe 1 is ejected from the gas ejection hole 8 of the first pipe 1 into the second pipe 2, as indicated by the thin arrow shown in FIG. A second gas Gb indicated by a dotted arrow is supplied to the second pipe 2 , and is mixed with the first gas Ga ejected from the gas ejection hole 8 in the second pipe 2 . The gas is ejected from the gas ejection hole 9 into the third pipe 3. Furthermore, the mixed gas is supplied to the outside of the apparatus from a gas ejection hole 10 formed in the third pipe 3.

Note that the gas ejection holes 8 formed in the first pipe 1 and the gas ejection holes 9 formed in the second pipe 2 are out of phase by 180° in the circumferential direction, that is, the gas ejection holes 9 are one space on the inner side. It is not located on the extension line of the gas ejection direction from the gas ejection hole 8 formed in the first pipe 1, which is a pipe. Therefore, the gas ejected from the gas ejection hole 8 does not directly eject from the gas ejection hole 9 to the third pipe 3. Therefore, within the second pipe 2, the first gas Ga and the second gas Gb are sufficiently mixed.

Moreover, with respect to the gas jet hole 9 formed in the second pipe 2, the gas jet hole 10 formed in the third pipe 3 is also the same as the gas jet hole 9 formed in the second pipe 2, which is one pipe inside. The phase is shifted by 180° in the circumferential direction. Therefore, the gases mixed in the second pipe 2 are further mixed in the process of passing through the third pipe 3. In this way, by passing the mixed gas through the third pipe, which is the outermost pipe, the mixed gas can be sufficiently mixed in the inner space of the third pipe 3. As a result, the mixed gas ejected from the gas ejection hole 10 is a uniform mixture of the two types of gases Ga and Gb.

Further, in the first embodiment, the multiple pipe structure can simultaneously realize the functions of a gas supply path and a mixing container, and the device can be made more compact. For example, a gas mixture device A in which the first and second pipes 1 and 2 are built into the third pipe 3 having an outer diameter of 34 [mm] can inject a mixed gas at a flow rate of 100 [L/min].

Furthermore, in the first embodiment, in the multiple pipe structure, the opening area of one gas nozzle 8, 9, 10 in each pipe is increased in the order of gas nozzle 8, 9, 10, and the gas in each pipe is Since the total opening area of the nozzle holes is set to increase from the innermost pipe to the outermost pipe, the gas does not flow back toward the inner pipe, and the third pipe 3 is the outermost pipe. Mixed gas can be spouted smoothly from the

In addition, in order to make the total opening area of the gas nozzles 8, 9, 10 in each pipe 1, 2, 3 increase in the order from the first pipe 1 to the third pipe 3, one gas nozzle In addition to adjusting the opening area of the gas outlet, it can also be adjusted by changing the number of gas ejection holes.
However, if at least the sum of the opening areas of the outermost pipe is made larger than the sum of the opening areas of each of the other pipes, the It is possible to make the mixed gas blow out smoothly from the outer pipe.

Furthermore, in the first embodiment, of the first pipe 1 and the second pipe 2 provided with the gas supply ports 6 and 7, the second pipe 2 having a large capacity is supplied with the second gas Gb having a large supply flow rate. , the first gas Ga with a small supply flow rate is supplied to the first pipe 1 with a small capacity. In this way, the second gas Gb having a large supply flow rate is supplied to the second pipe 2 having a large capacity, so that backflow of gas does not occur, and more efficient gas mixing can be achieved by smooth gas flow.

[Second embodiment]
A second embodiment will be described using FIG. 3. FIG. 3 is a diametrical cross-sectional view of the second embodiment.
The second embodiment is a gas mixing device B that generates a mixed gas of three types of gases.
The gas mixing device B shown in FIG. 3 has a multilayer structure including a fourth pipe 4 and a fifth pipe 5 on the outside of the first to third pipes 1 to 3 similar to the first embodiment.
Therefore, in this second embodiment, the fifth pipe 5 is the outermost pipe.

One end side of the fourth and fifth pipes 4 and 5 is closed with a cap (not shown), similar to the first to third pipes 1 to 3 shown in FIG. The end side is closed with a cap having a through hole in the center like the caps 2b and 3b shown in FIG.
Further, in the second embodiment, a gas supply port (not shown) is provided in the fourth pipe 4 to supply the third gas Gc.

Gas ejection holes 8, 9, 10, 11, and 12 are formed in a line in the length direction of each of the first to fifth pipes 1 to 5, respectively. These gas ejection holes 8, 9, 10, 11, and 12 also maintain a positional relationship in which the diametrically adjacent pipes are shifted in phase by 180° in the circumferential direction, as in the first embodiment. Further, the total opening area of each pipe is set to increase in the order from the first pipe 1, which is the innermost pipe, to the fifth pipe 5, which is the outermost pipe.

[Action/effect, etc.]
In the second embodiment, as shown in FIG. 3, the first gas Ga is supplied to the first pipe 1, the second gas Gb is supplied to the second pipe 2, and the third gas Gc is supplied to the fourth pipe 4. A mixed gas of these three types of gases is ejected from the gas ejection hole 12 of the fifth pipe 5.
In this second embodiment, the gas Ga supplied to the first pipe 1 is ejected from the gas ejection hole 8 into the second pipe 2, and in the process of reaching the gas ejection hole 9 of the second pipe 2, the gas Ga is ejected from the second pipe 2. The gas Gb is mixed with the second gas Gb supplied to the second gas Gb.

The mixed gas of the first gas Ga and the second gas Gb is ejected from the gas ejection hole 9 of the second pipe 2 into the third pipe 3 . Since this third pipe 3 is not provided with a gas supply port and no new gas is supplied, the mixed gas of the two types of gas passes through the inside of the third pipe 3 and is ejected from the gas ejection hole 10. Gases Ga and Gb are uniformly mixed.
This mixed gas is ejected into the fourth pipe 4, merges with the third gas Gc supplied to the fourth pipe 4 as indicated by the wavy arrow, and is ejected from the gas ejection hole 11 to the fifth pipe 5.

Also in this second embodiment, the multiple pipe structure can simultaneously realize the functions of a gas supply path and a mixing container, and the device can be made more compact.
In the second embodiment, the number of pipes is two more than the number of gas types to be mixed, and a gas supply port is not provided not only in the fifth pipe 5, which is the outermost pipe, but also in the third pipe 3. The mixed gas is stirred in the inner space of these pipes to generate a more uniform mixed gas.
However, if the number of pipes forming the multiplex structure increases, the device will become larger, so in order to make the device more compact, the multiplex structure should be formed with one more pipe than the number of gas types to be supplied. Preferably, the outermost pipe is provided with no gas supply port.

In the first and second embodiments, the smaller the distance between the pipes in the diametrical direction, the more the gas flow flowing between them can be stirred, and the more uniform the gas flow can be. However, since the flow path resistance increases accordingly, it is preferable to select the diameter of each pipe and the distance between the pipes depending on the required amount of mixed gas.

In addition, the positional relationship of the gas ejection holes of adjacent pipes in the diametrical direction does not need to be located on the extension line of the gas ejection direction of the gas ejection hole of the one inner pipe, and as described above, °It is not limited to those that shift the phase. For example, without shifting the phase in the circumferential direction, by shifting the positions of the gas nozzles on the inner pipe and the gas nozzles on the outer pipe in the pipe length direction, The gas ejection holes of the pipes may not face each other.
Furthermore, in the embodiment described above, the gas ejection holes formed in each pipe are arranged in a line, but the arrangement of the gas ejection holes is not limited to one line. They may be arranged irregularly across the sides of the pipe.

However, if the gas ejection holes are formed in a linear area along the length of each pipe, workability will be improved. In the linear area, the gas ejection holes may be arranged not only in one row, but also in two rows, or in a staggered manner. Furthermore, as described above, by arranging gas ejection holes in a line within a linear area, workability can be further improved.

[Third embodiment]
FIG. 4 is a schematic configuration diagram of a discharge treatment apparatus according to a third embodiment. This third embodiment is a discharge treatment apparatus using the gas mixing device A of the first embodiment.
The discharge processing apparatus of the third embodiment includes, in a processing chamber 13, a support member 14 that supports a processing object w, and a discharge electrode 15 that faces the processing object w above the support member 14. A power source 16 is connected to the discharge electrode 15, and by applying a high voltage from the power source 16 to the discharge electrode 15, a discharge is generated in the discharge space S. The surface of the object w to be treated is modified by this discharge energy. Note that the power source 16 may be provided outside the processing chamber 13.

Further, a gas mixing device A shown in FIGS. 1 and 2 is provided near the discharge space S, that is, near the discharge electrode. This gas mixing device A includes gas supply ports 6 and 7 in a first pipe 1 and a second pipe 2 (see FIGS. 1 and 2). Air is supplied to the gas supply port 6 as the first gas Ga, and nitrogen gas is supplied to the gas supply port 7 as the second gas Gb. Then, the supply flow rates of air and nitrogen gas are adjusted so that a mixed gas adjusted to a predetermined oxygen concentration lower than that of the atmosphere is ejected from the gas ejection hole 10 of the third pipe 3.
In the third embodiment, the flow rate of nitrogen gas supplied to the second pipe 2 is made larger than the flow rate of air supplied to the first pipe 1.

[Action/effect, etc.]
In this third embodiment, the air supplied to the first pipe 1 is ejected from the gas ejection hole 8 to the second pipe 2, and is mixed with the nitrogen gas supplied to the second pipe 2 within the second pipe 2. , and are uniformly mixed in the third pipe 3 and then injected toward the discharge space S.
The oxygen concentration of the mixed gas injected from the gas mixing device A is set by the ratio of the supply flow rates of the air supplied to the gas mixing device A and the nitrogen gas. Since air and nitrogen gas are uniformly mixed, temporal and spatial variations in oxygen concentration within the discharge space S can be reduced. In fact, it has been confirmed that the variation in oxygen concentration can be controlled to within 5%.

In this way, since the oxygen concentration in the discharge space can be accurately controlled, the discharge current value can also be accurately controlled.
In order to control the discharge current value, it is also possible to control the position of the discharge electrode 15 and the voltage applied to the discharge electrode 15. However, if a mechanism for changing the position of the discharge electrode 15 is provided, the inside of the processing chamber becomes complicated, and it is difficult to finely control the applied voltage using the power source 16.

On the other hand, in order to control the oxygen concentration in the discharge space S, the amount of gas supplied to the gas mixing device A may be controlled on the gas supply source side. The gas mixing device A is a compact device as described above, and in order to control the oxygen concentration in the discharge space S, the gas mixing device A does not require the processing chamber 13 to be enlarged or have a complicated internal structure. There is no need to worry.

Note that the gas mixing device installed in the processing chamber 13 is not limited to the gas mixing device A of the first embodiment, but can be provided with a multiple structure according to the number of mixed gases required. Further, the structure of the discharge electrode is not particularly limited either.
Further, the object to be treated and its support member are not limited to this embodiment, and the discharge treatment includes treatments such as surface modification, static elimination, and charging.

The gas mixing device of the present invention is useful in various situations that require a uniform gas mixture.

1, 2, 3, 4, 5 1st to 5th pipes 8, 9, 10, 11, 12 Gas injection hole 13 Processing chamber 15 Discharge electrode 16 Power supply

Claims (5)

A gas mixing device for mixing multiple types of gas,
A multiple structure in which pipes each having a different diameter and a number greater than the number of gas types to be mixed are arranged in multiple layers, and the pipes are cut off from communication with other pipes at their ends;
A plurality of gas ejection holes formed on the side of each of the pipes,
A pipe other than the outermost pipe constituting the outermost layer among the plurality of pipes for supplying each of the plurality of gases to be mixed is provided, and each of the plurality of gases to be mixed is supplied to the pipe. Equipped with a gas supply port to supply each
Each of the gas injection holes in a pipe other than the innermost pipe constituting the innermost layer among the plurality of pipes is a gas injection hole formed in a pipe one pipe inside of the pipe in which the gas injection hole is formed. Formed at a position other than the extension line of the ejection direction,
A gas mixing device configured such that a mixed gas of gases supplied from the gas supply port is homogenized in an inner space of the outermost pipe and is ejected to the outside from a gas ejection hole of the outermost pipe. The number of pipes that make up the above multiplexed structure is
The gas mixing device according to claim 1, wherein the number of gases is one more than the number of gases to be mixed. 3. The gas mixing device according to claim 1, wherein the total opening area of each pipe in which the gas ejection holes are formed is set such that the total opening area of the outermost pipe is maximum. The gas ejection hole is formed on the side of each pipe in a linear area along the length of the pipe,
The gas according to claim 1 or 2, wherein linear areas in which the gas ejection holes are formed between pipes adjacent in the diametrical direction are provided at positions shifted by 180° in phase in the circumferential direction of the pipe. Mixing equipment. The gas mixing device according to claim 1 or 2 is provided in a processing chamber equipped with a discharge electrode to which a high voltage is applied, and the mixed gas ejected from the gas mixing device is transferred to a discharge space near the discharge electrode. A discharge treatment device that emits water.

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