ULTRASONIC ATOMIZATION APPARATUS

An ultrasonic atomization apparatus according to the present disclosure includes a non-contact mist supply pipe that is provided above an atomization container without being in contact with the atomization container including a mist output pipe and a leakproof tank that is connected to the mist output pipe without being in contact with the non-contact mist supply pipe. The leakproof tank contains a sealing proper liquid. In this case, the sealing proper liquid is contained in a liquid containing space formed between the leakproof tank and the mist output pipe.

TECHNICAL FIELD

The present disclosure relates to an ultrasonic atomization apparatus that

atomizes a material solution using an ultrasonic transducer to obtain material solution mist.

BACKGROUND ART

As a deposition apparatus that sprays material solution mist obtained by atomizing (misting) a material solution onto a base material, such as a substrate, to obtain a functional thin film, an ultrasonic atomization apparatus that applies ultrasonic vibration to the material solution to generate the material solution mist has been used. In the ultrasonic atomization apparatus, the material solution mist generated in a material solution container is supplied from the material solution container to a mist jet, such as a nozzle, by a transport gas, and is sprayed from the mist jet onto the base material to form the thin film. One example of such a conventional ultrasonic atomization apparatus is an atomization apparatus disclosed in Patent Document 1.

To form a stable and uniform thin film on the base material, it is necessary to stabilize the amount of the material solution mist supplied from the ultrasonic atomization apparatus, so that it is necessary to accurately understand the amount of mist supplied from the ultrasonic atomization apparatus per unit time.

FIG.5is an illustration schematically showing an ultrasonic atomization apparatus300as a conventional first configuration. An XYZ Cartesian coordinate system is shown inFIG.5. The configuration of the conventional ultrasonic atomization apparatus300will be described below with reference toFIG.5.

In the ultrasonic atomization apparatus300, a material solution container includes an atomization container1and a separator cup12. A bottom surface of the material solution container is the separator cup12. The material solution container including the atomization container1and the separator cup12as described above contains a material solution15.

A pipe portion1A is provided above the separator cup12to communicate with the top of the atomization container1. A pipe outlet1X of the pipe portion1A is connected to an unillustrated mist jet, such as a nozzle, via an unillustrated mist supply pipe. Material solution mist MT generated in the material solution container of the ultrasonic atomization apparatus300is thus supplied to the mist jet via the pipe portion1A and the mist supply pipe.

The ultrasonic atomization apparatus300further includes a water tank10for containing therein ultrasonic transmission water9as an ultrasonic transmission medium. The water tank10and the separator cup12are positioned so that a bottom surface of the separator cup12is submerged in the ultrasonic transmission water9.

A plurality of ultrasonic transducers2are provided at a bottom surface of the water tank10located below the separator cup12. Two ultrasonic transducers2are illustrated inFIG.5. The plurality of ultrasonic transducers2include respective ultrasonic diaphragms2T and perform ultrasonic vibration operation to generate, from the ultrasonic diaphragms2T, ultrasonic waves W2having sizes matching planar shapes of the ultrasonic diaphragms2T.

A gas supply pipe4as a transport gas supply pipe is provided to an upper side surface of the atomization container1, and a transport gas G4is supplied from the gas supply pipe4to an internal space1H of the atomization container1. An unillustrated gas control device is attached to the gas supply pipe4, and a flow rate of the transport gas G4supplied to the atomization container1is controlled by the gas control device.

A gas supply pipe3as a diluent gas supply pipe is provided to a side surface of the pipe portion1A, and a diluent gas G3is supplied from the gas supply pipe3. An unillustrated gas control device is attached to the gas supply pipe3, and a flow rate of the diluent gas G3supplied into the pipe portion1A is controlled by the gas control device.

As described above, the material solution container including the atomization container1and the separator cup12contains the material solution15. The bottom surface of the material solution container is the separator cup12.

A material tank35is further provided independently of the material solution container including the atomization container1and the separator cup12. The material tank35contains therein the material solution15to be supplied to the material solution container. A material solution supply pipe31is provided between the material solution container and the material tank35. The material solution15can be supplied from the material tank35to the material solution container via the material solution supply pipe31.

A material solution supply mechanism8including a suction pump32and a flowmeter33is provided along the material solution supply pipe31.

The ultrasonic atomization apparatus300as the conventional first configuration further includes a scale51that measures the weight of the material tank35and the material solution15in the material tank35as a measurement target. The scale51as a weight measuring instrument can measure the weight of the measurement target as a measured weight.

The material solution supply mechanism8and the material solution supply pipe31are excluded from the measurement target of the scale51. For example, the suction pump32and the flowmeter33are installed on another mount not to affect weight measurement performed by the scale51. However, a portion of the material solution supply pipe31from the flowmeter33to the material tank35(hereinafter abbreviated to a “supply pipe measurement target portion”) is included in the measurement target of the scale51.

The weight of the above-mentioned supply pipe measurement target portion, however, has a constant value, so that a change in weight of the measurement target can accurately be measured even though the supply pipe measurement target portion is included in the measurement target. The ultrasonic atomization apparatus300thus has no particular problem as the amount of the material solution15supplied to the material solution container can be estimated from the change in weight of the measurement target measured by the scale50.

The ultrasonic atomization apparatus300can obtain the amount of the material solution15supplied from the material tank35to the material solution container based on the measured weight measured by the scale51.

That is to say, the amount of the material solution15supplied from the material tank35to the material solution container can be obtained based on reduction in weight ΔP12(=P1−P2), where P1is the measured weight of the measurement target at time t1, P2is the measured weight of the measurement target at time t2after the time t1.

The amount of the supplied material solution15has a value indirectly indicating the amount of the supplied material solution mist MT. This is because it can be inferred that the amount of the supplied material solution15matches the amount of the material solution15consumed in the atomization container1, and the material solution mist MT in an amount matching the amount of the consumed material solution15is generated.

The ultrasonic atomization apparatus300can thus obtain the amount of the supplied material solution mist MT from the amount of the supplied material solution15obtained based on the measured weight of the measurement target measured by the scale51.

In the conventional ultrasonic atomization apparatus300having such a configuration, when the plurality of ultrasonic transducers2including the respective ultrasonic diaphragms2T perform the ultrasonic vibration operation to apply ultrasonic vibration, a vibration energy of the ultrasonic waves W2from the plurality of ultrasonic transducers2is transmitted to the material solution15in the material solution container via the ultrasonic transmission water9and the separator cup12.

Then, as illustrated inFIG.5, liquid columns6rise from a liquid level15A, the material solution15transitions to drops and mist, and the material solution mist MT can be obtained in the internal space1H of the atomization container1. As described above, the ultrasonic transducers2perform the ultrasonic vibration operation to apply the ultrasonic waves W2to atomize the material solution15to thereby generate the material solution mist MT.

The material solution mist MT generated in the atomization container1during performance of the ultrasonic vibration operation flows in the pipe portion1A along a mist output direction DM by the transport gas G4supplied from the gas supply pipe4and then is supplied from the pipe outlet1X of the pipe portion1A to the mist supply pipe and the mist jet.

A gas system connected to the conventional ultrasonic atomization apparatus300includes two gas systems for the transport gas G4and the diluent gas G3. The diluent gas G3is a gas to maintain the total amount of gas of the material solution mist MT ejected from the mist jet, such as the nozzle, constant.

The material solution mist MT generated in the internal space1H of the atomization container1by the ultrasonic vibration operation of the plurality of ultrasonic transducers2is supplied from the pipe outlet1X of the pipe portion1A outside the atomization container1to the mist supply pipe and the mist jet, which are not illustrated, by the diluent gas G3and the transport gas G4. In a case where the amount of the material solution mist MT generated in the internal space1H of the atomization container1is maintained constant, the amount of the material solution mist MT supplied from the atomization container1to the mist jet can be increased and reduced by a transport gas flow rate LC of the transport gas G4supplied from the gas supply pipe4.

On the other hand, in formation of the thin film using the material solution mist MT, not only a stable amount of mist but also a constant total gas flow rate LT of the material solution mist MT output from the mist jet is necessary. This is because, when the total gas flow rate LT is maintained constant, a spray speed of the material solution mist MT ejected from the mist jet can be maintained constant. An opening of the nozzle as the mist jet is slit-shaped, for example.

As described above, the material solution mist MT is supplied to the outside of the atomization container1by the transport gas G4. With the transport (delivery) of the material solution mist MT to the outside, the material solution15in the material solution container is reduced. It is necessary to maintain the amount of the material solution15in the material solution container constant to stabilize the amount of generated mist. This is because the amount of the generated material solution mist MT varies depending on the liquid level15A of the material solution15from the plurality of ultrasonic transducers2.

Thus, the liquid level15A of the material solution15in the material solution container is detected using a liquid level detector19, the amount of the reduced material solution15is obtained based on the liquid level15A, and the material solution15is supplied from the material tank35according to the amount of the reduced material solution15as appropriate. That is to say, the material solution15is supplied from the material tank35via the material solution supply pipe31to compensate for the amount of the reduced material solution15in the material solution container.

Due to the supply of the material solution15from the material tank35, the liquid level15A of the material solution15in the material solution container is maintained constant, so that the amount of the material solution15supplied from the material tank35eventually becomes equal to the amount of the reduced material solution15in the material solution container. The ultrasonic atomization apparatus300thus estimates the amount of the generated material solution mist MT based on the amount of the material solution15supplied from the material tank35.

As described above, the ultrasonic atomization apparatus300as the conventional first configuration measures the amount of the generated material solution mist MT, that is, the amount of mist supplied to the mist jet based on the amount of the material solution15supplied from the material tank35to stabilize a process of generating the material solution mist MT.

On the other hand, in a case where the transport gas flow rate LC is increased and reduced to control the amount of the supplied material solution mist MT, the total gas flow rate LT of the material solution mist MT is increased and reduced accordingly.

It is thus necessary to supply the diluent gas G3in a different system from the transport gas G4from the gas supply pipe3to the pipe portion1A near the atomization container1as illustrated inFIG.6to maintain the total gas flow rate LT constant. The relationship among the transport gas flow rate LC, a diluent gas flow rate LD, and the total gas flow rate LT is herein determined by an equation (1) below, where LD is the flow rate of the diluent gas G3.

Each of the transport gas flow rate LC, the diluent gas flow rate LD, and the total gas flow rate LT indicates the volume amount per unit time and is represented in units of “1 (liters)/min”, for example.

For example, in a case where the transport gas flow rate LC is reduced by ALC to reduce the amount of the supplied material solution mist MT, the total gas flow rate LT can be maintained constant by increasing the diluent gas flow rate LD by ALC.

As described above, the conventional ultrasonic atomization apparatus300can maintain the total gas flow rate LT of the material solution mist MT constant regardless of a change in transport gas flow rate LC by adding a diluent gas system for the diluent gas G3.

FIG.6is an illustration schematically showing an ultrasonic atomization apparatus301as a conventional second configuration. The XYZ Cartesian coordinate system is shown inFIG.6. The configuration of the ultrasonic atomization apparatus301as the conventional second configuration will be described below with reference toFIG.6. Components of the ultrasonic atomization apparatus301similar to those of the ultrasonic atomization apparatus300illustrated inFIG.5bear the same reference signs as those of the similar components, and description thereof is omitted as appropriate.

Although not illustrated inFIG.6, the ultrasonic atomization apparatus301includes the material solution supply pipe31, the material solution supply mechanism8, and the material tank35for containing the material solution15as with the ultrasonic atomization apparatus300. The ultrasonic atomization apparatus301, however, does not include the scale51that measures the weight of the material tank35and the material solution15as the measurement target.

The ultrasonic atomization apparatus301as the conventional second configuration includes a scale52that measures the weight of the material solution container (the atomization container1+the separator cup12), the water tank10, the plurality of ultrasonic transducers2, the material solution15in the atomization container1, and the ultrasonic transmission water9in the water tank10as the measurement target. The scale52as a weight measuring instrument measures the weight of the measurement target as a measured weight.

The gas supply pipe3, the gas supply pipe4, and the material solution supply pipe31are excluded from the measurement target of the scale52. For example, a plurality of support points are provided to the gas supply pipe3, the gas supply pipe4, and the material solution supply pipe31, and the gas supply pipe3, the gas supply pipe4, and the material solution supply pipe31are suspended at the plurality of support points to be stably supported. As a result, the gas supply pipe3, the gas supply pipe4, and the material solution supply pipe31can be excluded from the measurement target of the scale52.

The scale52as the weight measuring instrument supports the water tank10from the bottom surface of the water tank10using a support member53without being in contact with the plurality of ultrasonic transducers2and measures the weight of the measurement target including the material solution container (the atomization container1+the separator cup12), the plurality of ultrasonic transducers2, the water tank10, the material solution15, and the ultrasonic transmission water9.

The ultrasonic atomization apparatus301can obtain the amount of the material solution15consumed in the material solution container based on the measured weight measured by the scale52.

That is to say, the amount of the material solution15consumed in the material solution container can be obtained from the reduction in weight ΔP12(=P1−P2), where P1is the measured weight of the measurement target at the time t1, P2is the measured weight of the measurement target at the time t2after the time t1. In this case, it can be inferred that the material solution mist MT in an amount matching the amount of the consumed material solution15is generated.

The ultrasonic atomization apparatus301as the conventional second configuration can thus obtain the amount of the supplied material solution mist MT from the amount of the consumed material solution15measured based on the measured weight of the measurement target measured by the scale52.

PRIOR ART DOCUMENTS

Patent Document

SUMMARY

Problem to be Solved by the Invention

A first supplied mist amount measurement method for use in the ultrasonic

atomization apparatus300as the conventional first configuration illustrated inFIG.5utilizes material solution supply characteristics of the material solution15in the material solution container being reduced as a result of supply of the material solution mist MT generated in the internal space1H of the atomization container1to the mist jet, and the material solution15being supplied from the material tank35to the material solution container at a timing of detection of the reduction.

The amount of the material solution15supplied from the material tank35for use in the ultrasonic atomization apparatus300is thus not information at the moment when the material solution mist MT is generated and supplied to the outside but delayed information. The amount of the supplied material solution15for use in the ultrasonic atomization apparatus300thus has a first problem of poor responsiveness as information to control the amount of supplied mist constant.

On the other hand, a second supplied mist amount measurement method for use in the ultrasonic atomization apparatus301as the conventional second configuration illustrated inFIG.6is a method of measuring the weight of the measurement target including the material solution15in the material solution container and estimating the amount of supplied mist from the change in weight. The second supplied mist amount measurement method thus solves the above-mentioned first problem.

However, the mist supply pipe to supply the mist to the mist jet, such as the nozzle, is connected to the pipe outlet1X of the pipe portion1A, and a rigid metal pipe and a fluororesin pipe are often used as the mist supply pipe as the mist supply pipe is required to have chemical resistance and mechanical strength. At least portion of the mist supply pipe is included in the measurement target of the scale52.

The mist supply pipe thus produces a weight distribution effect of the measured weight measured by the scale52, and thus the conventional ultrasonic atomization apparatus301has a second problem in that the weight of the measurement target cannot accurately be measured.

The weight distribution effect refers to characteristics of force to direct the atomization container1upward inFIG.6being applied as force to pull up the atomization container1when the mist supply pipe is attached to the pipe portion1A so that the weight of the measurement target cannot accurately be measured.

As described above, the conventional ultrasonic atomization apparatus including the ultrasonic atomization apparatus300and the ultrasonic atomization apparatus301has a problem in that the amount of the supplied material solution mist MT cannot responsively and accurately be obtained.

It is an object of the present disclosure to provide an ultrasonic atomization apparatus capable of solving a problem as described above and responsively and accurately obtaining the amount of supplied material solution mist.

Means to Solve the Problem

An ultrasonic atomization apparatus according to the present disclosure is an ultrasonic atomization apparatus including: a material solution container that has an internal space for containing a material solution and includes a mist output pipe at a top surface thereof; an ultrasonic transducer that is provided below the material solution container; a non-contact mist supply pipe that is provided above the material solution container without being in contact with the material solution container including the mist output pipe; a leakproof tank that is provided to be connected to the mist output pipe without being in contact with the non-contact mist supply pipe; and a weight measuring instrument that supports the material solution container from below and measures the weight of a measurement target including the material solution container, the ultrasonic transducer, the leakproof tank, and the material solution, wherein the material solution is misted by ultrasonic vibration operation of the ultrasonic transducer to generate material solution mist in the internal space, the non-contact mist supply pipe includes an overlapping pipe portion and a non-overlapping pipe portion other than the overlapping pipe portion, the overlapping pipe portion having a pipe overlapping region in which the overlapping pipe portion and an upper region of the mist output pipe overlap along a mist output direction, a pipe overlapping space being formed between the overlapping pipe portion and the upper region, a liquid containing space is formed between the leakproof tank and the mist output pipe, the liquid containing space containing a sealing liquid therein, the sealing liquid being present in the pipe overlapping space, the measurement target further including the sealing liquid, and the material solution mist flows in the mist output pipe and the non-contact mist supply pipe along the mist output direction and is output from the non-contact mist supply pipe.

Effects of the Invention

The non-contact mist supply pipe of the ultrasonic atomization apparatus according to the present disclosure does not have a contacting relationship with the material solution container including the mist output pipe and thus can relatively easily be excluded from the measurement target of the weight measuring instrument.

On the other hand, the material solution in the material solution container is included in the measurement target of the weight measuring instrument, and the weight of the measurement target excluding the material solution has a constant value. The amount of consumed material solution can thus be obtained from a change in weight of the measurement target with accuracy. In addition, there is no delay between the amount of the consumed material solution and the amount of the generated material solution mist.

As a result, the ultrasonic atomization apparatus according to the present disclosure can obtain the amount of the consumed material solution from the change in weight of the measurement target and responsively and accurately obtain the amount of the supplied material solution mist based on the amount of the consumed material solution during performance of the ultrasonic vibration operation.

In addition, the sealing liquid is present in the pipe overlapping space between the non-contact mist supply pipe and the leakproof tank, and a flow path of the material solution mist in the pipe overlapping space is sealed by the sealing liquid.

The ultrasonic atomization apparatus according to the present disclosure can thus suppress a mist leak phenomenon of leak of the material solution mist to the outside of the non-contact mist supply pipe via the pipe overlapping space.

The objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

DESCRIPTION OF EMBODIMENTS

FIG.1is an illustration schematically showing a configuration of an ultrasonic atomization apparatus201in Embodiment 1 of the present disclosure. An XYZ Cartesian coordinate system is shown inFIG.1. The configuration of the ultrasonic atomization apparatus201in Embodiment 1 will be described below with reference toFIG.1.

In the ultrasonic atomization apparatus201, a material solution container includes an atomization container1and a separator cup12. A bottom surface of the material solution container is the separator cup12. The material solution container including the atomization container1and the separator cup12as described above has an internal space1H for containing a material solution15.

A mist output pipe1tis provided above the separator cup12to communicate with a top surface of the atomization container1. That is to say, the atomization container1includes the mist output pipe1tat the top surface thereof.

The ultrasonic atomization apparatus201further includes a water tank10as a transmission medium tank for containing ultrasonic transmission water9as an ultrasonic transmission medium therein. The water tank10and the separator cup12are positioned so that a bottom surface of the separator cup12is submerged in the ultrasonic transmission water9. An end of the separator cup12is sandwiched between the atomization container1and the water tank10to integrally configure the atomization container1, the water tank10, and the separator cup12.

A plurality of ultrasonic transducers2are provided at a bottom surface of the

water tank10located below the separator cup12. Two ultrasonic transducers2are illustrated inFIG.1. The plurality of ultrasonic transducers2include respective ultrasonic diaphragms2T and perform ultrasonic vibration operation to generate, from the ultrasonic diaphragms2T, ultrasonic waves having sizes matching planar shapes of the ultrasonic diaphragms2T.

A gas supply pipe4is provided to an upper side surface of the atomization container1, and a transport gas G4is supplied from the gas supply pipe4as a transport gas supply pipe to the internal space1H in the atomization container1. An unillustrated gas control device is attached to the gas supply pipe4, and a transport gas flow rate LC as a flow rate of the transport gas G4supplied to the atomization container1is controlled by the gas control device.

A gas supply pipe3is provided to a side surface of the mist output pipe1t,and a diluent gas G3is supplied from the gas supply pipe3as a diluent gas supply pipe. An unillustrated gas control device is attached to the gas supply pipe3, and a diluent gas flow rate LD1as a flow rate of the diluent gas G3supplied into the mist output pipe1tis controlled by the gas control device.

A non-contact mist supply pipe40is provided above the atomization container1without being in contact with the atomization container1including the mist output pipe1t.The non-contact mist supply pipe40includes a downstream pipe portion41, a tapered pipe portion42, and a connection pipe portion43.

The connection pipe portion43is disposed to surround an upper region Alt of the mist output pipe1t.The connection pipe portion43thus has a pipe overlapping region R14in which the connection pipe portion43and the upper region Alt of the mist output pipe1toverlap along a mist output direction DM, and a pipe overlapping space SP14is formed between the connection pipe portion43and the upper region Alt. As described above, the connection pipe portion43is an overlapping pipe portion overlapping the upper region Alt.

On the other hand, the tapered pipe portion42and the downstream pipe portion41do not have the pipe overlapping region R14in which the tapered pipe portion42and the downstream pipe portion41overlap the upper region Alt along the mist output direction DM. That is to say, the tapered pipe portion42and the downstream pipe portion41are each a non-overlapping pipe portion other than the overlapping pipe portion.

The connection pipe portion43is a pipe portion having a constant inside diameter and extending in a Z direction inFIG.1, the tapered pipe portion42is a pipe portion having an inside diameter reduced in a +Z direction inFIG.1, and the downstream pipe portion41is a pipe portion having a constant inside diameter and extending in the Z direction inFIG.1. An inside diameter of a top end of the tapered pipe portion42matches the inside diameter of the downstream pipe portion41, and an inside diameter of a bottom end of the tapered pipe portion42matches the inside diameter of the connection pipe portion43.

As described above, the non-contact mist supply pipe40includes the connection pipe portion43, the tapered pipe portion42, and the downstream pipe portion41provided contiguously along the +Z direction. The downstream pipe portion41is located above the mist output pipe1tand is an extension in the +Z direction of the mist output pipe1t.

The connection pipe portion43has a sufficiently greater inside diameter than the mist output pipe1t,so that the pipe overlapping space SP14is formed between the connection pipe portion43and the upper region Alt of the mist output pipe1twithout the connection pipe portion43being in contact with the upper region Alt. On the other hand, the pipe overlapping space SP14is not formed between the mist output pipe1tand each of the tapered pipe portion42and the downstream pipe portion41each being the non-overlapping pipe portion.

The ultrasonic atomization apparatus201further includes a leakproof tank45that is provided to be connected to the mist output pipe1twithout being in contact with the non-contact mist supply pipe40. The leakproof tank45is a tank for containing a sealing liquid. The leakproof tank45has an opening45kat the center thereof and is connected to the mist output pipe1tso that the mist output pipe1textends through the opening45k. A bottom surface of the leakproof tank45is located below a leading end43tof the connection pipe portion43.

A liquid containing space SP45is thus formed between the leakproof tank45and the mist output pipe1t,and a sealing proper liquid16as the sealing liquid is contained in the liquid containing space SP45.

The sealing proper liquid16is contained in the liquid containing space SP45so that a liquid level16A of the sealing proper liquid16is higher than the leading end43tof the connection pipe portion43and is lower than an uppermost end1sof the mist output pipe1t.

The sealing proper liquid16is thus present in the pipe overlapping space SP14. That is to say, the non-contact mist supply pipe40is positioned without being in contact with the leakproof tank45itself excluding the sealing proper liquid16so that the leading end43tas a lower end of the connection pipe portion43is submerged in the sealing proper liquid16.

A region below the pipe overlapping space SP14is thus a space closed by the sealing proper liquid16. That is to say, a flow path of the material solution mist MT in the pipe overlapping space SP14is sealed by the sealing proper liquid16.

The sealing proper liquid16is a liquid having a higher specific gravity and a higher viscosity than water and being suitable for sealing of a space and is silicon-based oil, acetic acid, and the like, for example.

FIG.2is an illustration schematically showing a mist supply system including the non-contact mist supply pipe40. As illustrated inFIG.2, a pipe outlet40X of the non-contact mist supply pipe40and one end of a mist supply pipe5are connected. A nozzle17as the mist jet is connected to the other end of the mist supply pipe5.

A substrate18as a base material is disposed below the nozzle17. The substrate18is placed on an unillustrated mount, for example. The material solution mist MT supplied to the nozzle17as the mist jet is ejected from an unillustrated opening in a bottom surface of the nozzle17to a surface of the substrate18to form a thin film on the surface of the substrate18being heated. The opening of the nozzle17is slit-shaped, for example.

Although not illustrated inFIG.1, the ultrasonic atomization apparatus201in Embodiment 1 includes the material tank35provided independently of the material solution container including the atomization container1and the separator cup12similarly to the ultrasonic atomization apparatus300illustrated inFIG.5. As illustrated inFIG.5, the material tank35contains therein the material solution15to be supplied to the material solution container. The ultrasonic atomization apparatus201also includes the material solution supply pipe31and the material solution supply mechanism8similarly to the ultrasonic atomization apparatus300illustrated inFIG.5. The scale51that measures the weight of the measurement target including the material tank35, however, is not provided.

The ultrasonic atomization apparatus201in Embodiment 1 includes a scale50that measures the weight of the material solution container (the atomization container1+the separator cup12), the water tank10as the transmission medium tank, the leakproof tank45, the plurality of ultrasonic transducers2, the material solution15in the material solution container, the sealing proper liquid16in the liquid containing space SP45, and the ultrasonic transmission water9in the water tank10as the measurement target. The scale50as a weight measuring instrument measures the weight of the measurement target as a measured weight.

In the ultrasonic atomization apparatus201in Embodiment 1, for example, a plurality of support points are provided to the gas supply pipe3, the gas supply pipe4, and the material solution supply pipe31, and the gas supply pipe3, the gas supply pipe4, and the material solution supply pipe31are suspended at the plurality of support points to be stably supported. As a result, the gas supply pipe3, the gas supply pipe4, and the material solution supply pipe31can be excluded from the measurement target of the scale50.

The scale50as the weight measuring instrument supports the water tank10from the bottom surface of the water tank10using the support member53without being in contact with the plurality of ultrasonic transducers2. The scale50measures the weight of the measurement target including the material solution container (the atomization container1+the separator cup12), the plurality of ultrasonic transducers2, the water tank10as the transmission medium tank, the leakproof tank45, the material solution15, the ultrasonic transmission water9, and the sealing proper liquid16. As described above, the scale50supports the material solution container from below and measures the weight of the measurement target.

In the ultrasonic atomization apparatus201, the non-contact mist supply pipe40and the mist supply system illustrated inFIG.2do not have a contacting relationship with the atomization container1including the mist output pipe1tand thus can surely be excluded from the measurement target of the scale50.

The ultrasonic atomization apparatus201in Embodiment 1 can obtain the amount of the material solution15consumed in the material solution container based on the measured weight measured by the scale50.

That is to say, the ultrasonic atomization apparatus201in Embodiment 1 can

obtain the amount of the material solution15consumed in the material solution container from the reduction in weight ΔP12(=P1−P2), where P1is the measured weight of the measurement target at the time t1, P2is the measured weight of the measurement target at the time t2after the time t1.

The ultrasonic atomization apparatus201in Embodiment 1 can thus obtain the amount of the supplied material solution mist MT from the amount of the consumed material solution15obtained based on the change in measured weight of the measurement target measured by the scale50as with the ultrasonic atomization apparatus301illustrated inFIG.6.

In the ultrasonic atomization apparatus201in Embodiment 1 having such a configuration, when the plurality of ultrasonic transducers2including the respective ultrasonic diaphragms2T perform the ultrasonic vibration operation to apply ultrasonic vibration, a vibration energy of ultrasonic waves from the plurality of ultrasonic transducers2is transmitted to the material solution15in the material solution container via the ultrasonic transmission water9and the separator cup12.

Then, as illustrated inFIG.1, liquid columns6rise from a liquid level15A, the material solution15transitions to drops and mist, and the material solution mist MT can be obtained in the internal space1H of the atomization container1. As described above, the ultrasonic transducers2perform the ultrasonic vibration operation to apply the ultrasonic waves to atomize the material solution15to thereby generate the material solution mist MT.

The material solution mist MT generated in the internal space1H of the atomization container1during performance of the ultrasonic vibration operation flows in the mist output pipe1talong the mist output direction DM by the transport gas G4and the diluent gas G3. Even after being output from the pipe outlet1X of the mist output pipe1t,the material solution mist MT flows in the non-contact mist supply pipe40along the mist output direction DM by the transport gas G4and the diluent gas G3. The material solution mist MT is then supplied from the pipe outlet40X of the non-contact mist supply pipe40to the mist supply system including the mist supply pipe5and the nozzle17.

A gas system connected to the ultrasonic atomization apparatus201in Embodiment 1 includes two gas systems for the transport gas G4and the diluent gas G3. The diluent gas G3is a gas to maintain the total amount of gas of the material solution mist MT ejected from the mist jet, such as the nozzle17, constant.

The material solution mist MT generated in the internal space1H of the atomization container1by the ultrasonic vibration operation flows through the mist output pipe1t,the non-contact mist supply pipe40, and the mist supply pipe5outside the atomization container1by the diluent gas G3and the transport gas G4and is supplied to the nozzle17(mist jet). In this case, the material solution mist MT flows in the mist output pipe1tand the non-contact mist supply pipe40along the mist output direction DM (+Z direction).

In a case where the amount of the material solution mist MT generated in the internal space1H of the atomization container1is maintained constant, the amount of the material solution mist MT supplied from the atomization container1to the mist jet can be increased and reduced by the transport gas flow rate LC of the transport gas G4.

On the other hand, in formation of the thin film using the material solution mist MT, not only a stable amount of mist but also a constant total gas flow rate LT of the material solution mist MT supplied to the mist jet is necessary as described above. When the total gas flow rate LT is maintained constant, a spray speed of the material solution mist MT ejected from the mist jet can be maintained constant.

The material solution mist MT generated in the internal space1H by the ultrasonic vibration operation of the plurality of ultrasonic transducers2is supplied to the outside of the atomization container1by the transport gas G4and the diluent gas G3. With the transport of the material solution mist MT to the outside, the amount of the material solution15in the material solution container is reduced. As described above, it is necessary to maintain the amount of the material solution15in the material solution container constant to stabilize the amount of the generated material solution mist MT.

In a case where the transport gas flow rate LC of the transport gas G4is increased and reduced to control the amount of the supplied material solution mist MT, the total gas flow rate LT of the material solution mist MT is increased and reduced accordingly.

The gas supply pipe3is thus provided to the mist output pipe1tnear the atomization container1as illustrated inFIG.1, and the diluent gas G3in a different system from the transport gas G4is supplied from the gas supply pipe3as the diluent gas supply pipe to maintain the total gas flow rate LT constant.

As described above, the relationship among the transport gas flow rate LC of the transport gas G4, the diluent gas flow rate LD of the diluent gas G3, and the total gas flow rate LT of the material solution mist MT satisfies the above-mentioned equation (1).

As described above, the ultrasonic atomization apparatus201in Embodiment 1 can maintain the total gas flow rate LT constant using the diluent gas G3regardless of the change in transport gas flow rate LC.

The non-contact mist supply pipe40of the ultrasonic atomization apparatus201in Embodiment 1 does not have the contacting relationship with the atomization container1including the mist output pipe1tand the leakproof tank45and thus can relatively easily be excluded from the measurement target of the scale50as the weight measuring instrument.

On the other hand, the material solution15in the material solution container is included in the measurement target of the scale50as the weight measuring instrument, and the weight of the measurement target excluding the material solution15has a constant value.

Specifically, the total weight of the atomization container1, the separator cup12, the water tank10as the transmission medium tank, the leakproof tank45, the plurality of ultrasonic transducers2, the ultrasonic transmission water9, and the sealing proper liquid16has a constant value. The weight of the ultrasonic transmission water9is not increased and reduced by the ultrasonic vibration operation.

The ultrasonic atomization apparatus201in Embodiment 1 can thus obtain the amount of the material solution15consumed in the material solution container from the change in weight of the measurement target with accuracy. In this case, there is no delay between the amount of the consumed material solution15and the amount of the generated material solution mist MT.

As a result, the ultrasonic atomization apparatus201in Embodiment 1 can obtain the amount of the consumed material solution15from the change in weight of the measurement target and responsively and accurately obtain the amount of the supplied material solution mist MT based on the amount of the consumed material solution15during performance of the ultrasonic vibration operation of the plurality of ultrasonic transducers2.

In addition, the pipe overlapping space SP14is formed between the connection pipe portion43as the overlapping pipe portion and the upper region Alt of the mist output pipe1t,and the sealing proper liquid16is present in the region below the pipe overlapping space SP14.

The region below the pipe overlapping space SP14is thus the space closed by the sealing proper liquid16. That is to say, the flow path of the material solution mist MT in the pipe overlapping space SP14is sealed by the sealing proper liquid16.

The ultrasonic atomization apparatus201in Embodiment 1 can thus effectively suppress a mist leak phenomenon of leak of the material solution mist MT to the outside of the non-contact mist supply pipe40via the pipe overlapping space SP14.

Furthermore, the ultrasonic atomization apparatus201in Embodiment 1 uses the sealing proper liquid16having a higher specific gravity and a higher viscosity than water as the sealing liquid to enhance an effect of suppressing the above-mentioned mist leak phenomenon.

In addition, the ultrasonic atomization apparatus201in Embodiment 1 uses a double-chamber scheme including the water tank10as the transmission medium tank and the material solution container (the atomization container1+the separator cup12), and the measurement target of the scale50further includes the separator cup12, the water tank10, and the ultrasonic transmission water9(ultrasonic transmission medium). The ultrasonic atomization apparatus201using the double-chamber scheme can thus responsively and accurately obtain the amount of the supplied material solution mist MT.

FIG.3is an illustration schematically showing a configuration of an ultrasonic atomization apparatus202in Embodiment 2 of the present disclosure. The XYZ Cartesian coordinate system is shown inFIG.3. The configuration of the ultrasonic atomization apparatus202in Embodiment 2 will be described below with reference toFIG.3. A portion similar to that of the ultrasonic atomization apparatus201in Embodiment 1 illustrated inFIG.1bear the same reference sign as that of the similar portion, and description thereof is omitted as appropriate.

In the ultrasonic atomization apparatus202in Embodiment 2, the material solution15is contained in the liquid containing space SP45as the sealing liquid.

As with the sealing proper liquid16in Embodiment 1, the material solution15is also present in the pipe overlapping space SP14. The pipe overlapping space SP14is thus a space closed by the material solution15.

In the ultrasonic atomization apparatus202in Embodiment 2, the material solution15is contained in a limited capacity state in which the liquid containing space SP45of the leakproof tank45is full of the material solution15. Specifically, the leakproof tank45contains the material solution15in the liquid containing space SP45so that a liquid level15A of the material solution15matches the uppermost end1sof the mist output pipe1t.

The material solution15is thus contained in the liquid containing space SP45in the limited capacity state in which the material solution15reaches the uppermost end1sof the mist output pipe1tin the pipe overlapping space SP14.

A path from the pipe overlapping space SP14to the internal space1H of the material solution container via the mist output pipe1tis herein defined as a liquid flow path.

As the material solution15, a first material solution and a second material solution described below are considered. The first material solution is a material solution obtained by dissolving many solutes in water (a solvent). The first material solution has a higher viscosity and a higher specific gravity than water.

The second material solution is a material solution obtained by dissolving a solute in an organic solvent, such as methanol, as a solvent. The second material solution has a lower viscosity and a lower specific gravity than water.

As the solute for each of the first material solution and the second material solution, a metal complex (e.g., zinc acetate and aluminum acetate) is considered, for example. The amount of the solute used for the second material solution, however, is set to an amount in a range in which the second material solution has a lower viscosity and a lower specific gravity than water.

The ultrasonic atomization apparatus202in Embodiment 2 includes a supply system for the material solution15including the material solution supply mechanism8, the material solution supply pipe31, and the material tank35as in Embodiment 1. In the ultrasonic atomization apparatus202in Embodiment 2, however, the material solution supply pipe31is provided not to the material solution container but to the leakproof tank45in contrast to Embodiment 1. Description will be made in this respect below.

The material tank35is provided independently of the material solution container and the leakproof tank45. The material tank35contains therein the material solution15to be supplied to the material solution container via the leakproof tank45. A material solution supply pipe31is provided between the leakproof tank45and the material tank35. The material solution15can be supplied from the material tank35to the leakproof tank45via the material solution supply pipe31.

The material solution supply mechanism8including the suction pump32and the flowmeter33is provided along the material solution supply pipe31.

FIG.4is an illustration schematically showing a configuration of a flow rate control system for the material solution15in the ultrasonic atomization apparatus202in Embodiment 2. As illustrated inFIG.4, the flow rate control system includes the scale50, the material solution supply mechanism8, and a flow rate controller60as main components. The material solution supply mechanism8includes the suction pump32and the flowmeter33.

The flowmeter33measures a flow rate through the material solution supply pipe31to obtain flow rate information S33indicating the measured flow rate. The scale50measures the weight of the measurement target and outputs measured weight information S50indicating the weight.

The flow rate controller60receives the flow rate information S33from the flowmeter33and receives the measured weight information S50from the scale50. The flow rate controller60thus always recognizes the flow rate through the material solution supply pipe31by the measured flow rate indicated by the flow rate information S33.

The flow rate controller60can always obtain the amount of the material solution15consumed in the material solution container from the change in measured weight indicated by the measured weight information S50. In a case where the material solution15is supplied from the material tank35to the leakproof tank45, the flow rate controller60can obtain the amount of the supplied material solution15from the measured flow rate indicated by the flow rate information S33and can accurately obtain the amount of the consumed material solution15by taking the amount of the supplied material solution15into account.

The flow rate controller60can thus perform material supply control processing of outputting a control signal SC32indicative of the amount of drive of the suction pump32to compensate for the amount of the material solution15consumed in the internal space1H based on the flow rate information S33and the measured weight information S50.

As described above, the flow rate controller60performs the material supply control processing of controlling material solution supply operation to supply the material solution15to leakproof tank45with respect to the material solution supply mechanism8including the suction pump32and the flowmeter33.

When the material solution supply mechanism8performs the material solution supply operation, the material solution15is supplied to the leakproof tank45. The amount of the material solution15supplied by the material solution supply operation is herein referred to as a supplied material solution amount SL45.

As described above, the leakproof tank45contains the material solution15in the liquid containing space SP45in the limited capacity state. Thus, when the material solution15is supplied to the leakproof tank45by the material solution supply operation, the same amount of the material solution15as the supplied material solution amount SL45is supplied into the internal space1H of the material solution container via the above-mentioned liquid flow path.

Specifically, the material solution15in the supplied material solution amount SL45overflows from the liquid containing space SP45, flows along an inner wall of the mist output pipe1t,and then falls from the mist output pipe1tto be supplied into the internal space1H.

The ultrasonic atomization apparatus201in Embodiment 1 performs the

material supply control processing of controlling the material solution supply operation to directly supply the material solution15to the material solution container with respect to the material solution supply mechanism8under control performed by the flow rate controller60as in Embodiment 2.

As described above, the ultrasonic atomization apparatus202in Embodiment 2 accurately recognizes the amount of the material solution15consumed in the material solution container based on the measured weight information S50obtained by the scale50and the flow rate information S33obtained by the flowmeter33. The ultrasonic atomization apparatus202obtains the amount of the supplied material solution mist MT from the amount of the consumed material solution15.

The non-contact mist supply pipe40of the ultrasonic atomization apparatus202in Embodiment 2 does not have the contacting relationship with the atomization container1including the mist output pipe1tand the leakproof tank45and thus can relatively easily be excluded from the measurement target of the scale50as the weight measuring instrument.

On the other hand, the material solution15in the material solution container is included in the measurement target of the scale50as the weight measuring instrument, and the weight of the measurement target excluding the material solution15has a constant value.

As a result, the ultrasonic atomization apparatus202in Embodiment 2 can obtain the amount of the consumed material solution15from the change in weight of the measurement target and responsively and accurately obtain the amount of the supplied material solution mist MT based on the amount of the consumed material solution15during performance of the ultrasonic vibration operation as in Embodiment 1.

Assume herein that the material solution15is supplied from the material tank35into the internal space1H of the material solution container via the leakproof tank45by the material solution supply operation performed by the material solution supply mechanism8.

In this case, the flow rate controller60can obtain the amount of the material solution15supplied from the material tank35to the leakproof tank45based on the flow rate information S33received from the flowmeter33of the material solution supply mechanism8and properly exclude the amount of the supplied material solution15from the change in weight of the measurement target.

Furthermore, in a case where the ultrasonic atomization apparatus202in Embodiment 2 uses the above-mentioned first material solution having a higher specific gravity and a higher viscosity than water as the sealing liquid, the effect of suppressing the above-mentioned mist leak phenomenon can be enhanced as in Embodiment 1.

In addition, in the ultrasonic atomization apparatus202in Embodiment 2, the material solution15is present in the pipe overlapping space SP14as the sealing liquid.

The flow path of the material solution mist MT in the pipe overlapping space SP14is thus sealed by the material solution15. The ultrasonic atomization apparatus202in Embodiment 2 can thus suppress the mist leak phenomenon of leak to the outside of the non-contact mist supply pipe40via the pipe overlapping space SP14.

In addition, the leakproof tank45contains the material solution15in the above-mentioned limited capacity state so that the material solution15can be supplied to the material solution container via the above-mentioned liquid flow path, and thus the material solution15can be supplied into the internal space1H of the material solution container via the above-mentioned liquid flow path.

The ultrasonic atomization apparatus202in Embodiment 2 can thus maintain a current of the material solution mist MT generated in the internal space1H constant as it is not necessary to provide the material solution supply pipe31in the internal space1H as in the ultrasonic atomization apparatus201in Embodiment 1.

The supply of the material solution15from the leakproof tank45via the above-mentioned liquid flow path does not adversely affect output of the material solution mist MT along the mist output direction DM in the mist output pipe1tas it is along the inner wall of the mist output pipe1t.

The ultrasonic atomization apparatus202in Embodiment 2 includes the material tank35independently of the material solution container and the leakproof tank45, and the material solution15is supplied from the material tank35into the internal space1H of the material solution container via the leakproof tank45. In this case, the leakproof tank45contains the material solution15in the limited capacity state in which the liquid level15A of the material solution15is the same as the level of the uppermost end1sof the mist output pipe1t.

In the ultrasonic atomization apparatus202in Embodiment 2, the same amount of the material solution15as the supplied material solution amount SL45from the material solution supply mechanism8to the leakproof tank45is supplied to the internal space1H of the material solution container via the above-mentioned liquid flow path.

Herein, a material solution15α is the material solution15in the material tank35, a material solution15β is the material solution15in the liquid containing space SP45of the leakproof tank45, and a material solution15γ is the material solution15in the internal space1H of the material solution container.

When the material solution15α is supplied from the material solution supply mechanism8into the liquid containing space SP45of the leakproof tank45, the same amount of the material solution15β as the amount of the supplied material solution15α is supplied into the internal space1H of the material solution container via the above-mentioned liquid flow path without delay. As a result, the same amount of the material solution15β as the amount of the supplied material solution15α is supplied to the material solution15γ in the internal space1H of the material solution container.

The ultrasonic atomization apparatus202in Embodiment 2 can thus supply the material solution15from the material tank35into the internal space1H of the material solution container via the above-mentioned liquid flow path with accuracy by causing the material solution supply mechanism8to perform the material solution supply operation under control performed by the flow rate controller60.

That is to say, the material solution15is indirectly supplied from the material tank35into the internal space1H of the material solution container under control performed by the flow rate controller60.

Furthermore, the ultrasonic atomization apparatus202in Embodiment 2 using the double-chamber scheme can responsively and accurately obtain the amount of the supplied material solution mist MT as in Embodiment 1.

While the present disclosure has been described in detail, the foregoing description is in all aspects illustrative and not restrictive. It is understood that numerous unillustrated modifications can be devised without departing from the scope of the present disclosure.

EXPLANATION OF REFERENCE SIGNS

1tmist output pipe

3,4gas supply pipe

5mist supply pipe

8material solution supply mechanism

16sealing proper liquid

40non-contact mist supply pipe

41downstream pipe portion

42tapered pipe portion

43connection pipe portion

60flow rate controller

MT material solution mist