JP2004313871A - Ultrasonic atomizer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensively producible ultrasonic atomizer where an almost fixed atomizing amount can be secured even if the driving voltage of a circuit and the properties of a vibrator are varied more or less. <P>SOLUTION: The ultrasonic atomizer is provided with: a driving circuit 10 of controlling the driving of the ultrasonic atomizer; a power source 11 of feeding power source voltage to the driving circuit 10; an ultrasonic vibrator 14 consisting of a piezoelectric element 12 and an ultrasonic horn 13; an atomizing liquid tank 15 of storing a liquid (L) to be atomized; and a fibrous strand 16 of feeding the liquid (L) from the atomizing liquid tank 15 to the ultrasonic vibrator 14. It is suitable that the fibrous strand 16 is arranged at a position deviated from the vicinity of the center of an atomization working face 13a in the ultrasonic vibrator, and twine of cotton is adopted as the fibrous strand 16. Further, a support for the ultrasonic vibrator 14 is made of metal, and a signal line is reduced by obtaining the electric power of the ultrasonic vibrator from the support, so that cost reduction is realized. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ultrasonic atomizer, and more particularly to an ultrasonic atomizer using a fiber bundle as a medium for supplying a liquid to an ultrasonic vibrator.
[0002]
[Prior art]
Conventionally, ultrasonic atomizers using ultrasonic transducers have been known for various uses such as a household atomizer for indoor humidification and a medical atomizer for atomizing a small amount of a chemical solution. I have. In the case of a household atomizer for indoor humidification, it is common to attach a piezoelectric vibrator to the bottom of a water tank filled with water, realizing a relatively large amount of atomization of about several hundred cc per hour. ing. On the other hand, a medical atomizer that atomizes a small amount of a chemical solution or the like is generally driven by a small power of 5 W or less, which is suitable for driving a battery. The structure of the ultrasonic atomizer suitable for such an application is, for example, by inserting a sponge into a container containing a liquid and bringing the upper end side surface of the sponge into contact with the horn portion of the ultrasonic vibrator so that the inside of the container is (See, for example, Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 05-212330
[Problems to be solved by the invention]
In recent years, as the applications of ultrasonic atomizers have expanded, the demands on the accuracy of the atomization amount (maintaining the spray amount per unit time, securing a stable spray amount, etc.) have become more and more severe. Ultrasonic atomizers cannot meet such demands. That is, the conventional ultrasonic atomizer controls the drive voltage of the ultrasonic oscillator to adjust the amplitude of the ultrasonic oscillator, and adjusts the amount of atomization. However, even if the drive voltage is set to a constant value for the purpose of keeping the amount of atomization constant, the amount of atomization depends on the individual characteristics of the ultrasonic vibrator. It has been very difficult to manufacture an ultrasonic atomizer so that there is no difference between the two. Even if the ultrasonic transducer is manufactured with strict standards set, it is difficult to keep the amount of atomization constant when the drive voltage fluctuates. Further, if the ultrasonic transducer is manufactured with such strict standards, the manufacturing cost is increased.
[0005]
The present invention has been made in order to solve the above-described problems, and even when the drive voltage of the circuit and the characteristics of the vibrator slightly vary, a substantially constant amount of atomization can be secured, and An ultrasonic atomizer characterized by being able to be manufactured at low cost.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the ultrasonic atomizer according to the present invention, by arranging the fiber bundle drawn out of the container containing the liquid on the atomizing action surface side of the ultrasonic oscillator, The liquid supplied from the fiber bundle by capillary action is atomized by an ultrasonic vibrator.
[0007]
Further, in the ultrasonic atomizer according to the present invention, the fiber bundle is arranged at a position deviated from the vicinity of the center of the atomizing action surface of the ultrasonic vibrator.
[0008]
Further, in the ultrasonic atomizer according to the present invention, it is preferable that the fiber bundle is a yarn.
[0009]
Still further, in the ultrasonic atomizer according to the present invention, a support of the ultrasonic vibrator is made of metal, and power of the ultrasonic vibrator is obtained from the support.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating a schematic configuration of an ultrasonic atomizer according to the present embodiment.
[0011]
The ultrasonic atomizer according to the present embodiment includes, as a driving unit, a driving circuit 10 that controls the driving of the ultrasonic atomizer, a power supply 11 that supplies a power supply voltage to the driving circuit 10, and a power supply from the power supply 11. And an ultrasonic vibrator 14 that vibrates when supplied. In addition, the ultrasonic vibrator 14 includes the piezoelectric element 12 and the ultrasonic horn 13. Further, the ultrasonic atomizer in the present embodiment serves as a liquid supply unit, a spray liquid tank 15 for storing a liquid (L) to be sprayed, and a liquid (liquid) from the spray liquid tank 15 to the ultrasonic vibrator 14. L) for supplying L).
[0012]
The oscillation signal from the drive circuit 10 is connected so as to be applied between the piezoelectric element 12 and the ultrasonic horn 13. The ultrasonic horn 13 has a cylindrical end, and the plane of the end forms a vibrating surface to form the atomizing surface 13a, which plays a role in generating mist.
[0013]
The fiber bundle 16 supplies the liquid to the atomizing surface 13a of the ultrasonic horn 13. The lower end of the fiber bundle 16 hangs down in the spray liquid tank 15, and the upper end is in contact with the atomizing surface 13 a of the ultrasonic horn 13. However, the fiber bundle 16 may always be in contact with the atomizing action surface 13a, or may be normally separated and contact the atomizing action surface 13a when the ultrasonic horn 13 of the ultrasonic vibrator 14 vibrates. It may be installed in. The liquid (L) to be sprayed stored in the spray liquid tank 15 rises along the fiber bundle 16 and is supplied to the atomizing surface 13 a of the ultrasonic horn 13. The principle by which the liquid (L) rises in the fiber bundle 16 is based on the known capillary phenomenon, and a description thereof will be omitted. The liquid (L) supplied to the atomizing surface 13 a of the ultrasonic horn 13 by the fiber bundle 16 is atomized by the vibration of the ultrasonic horn 13 and sprayed.
[0014]
The fiber bundle 16 for supplying the liquid (L) to the atomizing surface 13a of the ultrasonic horn 13 is covered by the pipe 17 from the spray liquid tank 15 to the atomizing surface 13a. The evaporation of the liquid (L) is prevented, and the liquid (L) can be efficiently supplied.
[0015]
Here, the positional relationship between the ultrasonic horn 13 and the fiber bundle 16 will be described. Although the liquid (L) is atomized by the vibration of the ultrasonic horn 13, the atomization of the liquid (L) is substantially performed on the atomizing action surface 13 a of the ultrasonic horn 13 by an experiment conducted by the present inventors. It has been found to take place near the center. Therefore, in order to efficiently atomize the liquid (L), it is preferable to dispose the fiber bundle 16 at a position outside the vicinity of the center of the atomizing action surface 13 a of the ultrasonic horn 13.
[0016]
Further, it is preferable to use a yarn as the fiber bundle 16 from which the most stable amount of atomization can be obtained by intensive efforts such as experiments by the present inventors, and it is even more preferable to use a twisted cotton yarn. I got the knowledge. The reason why the cotton twisted yarn is used as the liquid supply medium to the ultrasonic vibrator 14 is that the maximum amount of liquid supply per unit time is constant depending on the thickness, material, twisting method and the like of the yarn. It is because it can secure. This characteristic will be described with reference to FIG. 2. The maximum liquid transmission amount of the yarn varies depending on the type of the yarn (A, B, C). It is impossible to atomize the liquid (L) in excess of the liquid transmission amount. By setting the drive voltage of the device in advance in the saturated region (a) of the liquid transmission amount of the yarn, a constant atomization amount (b1, b2, b3) can be obtained. Therefore, by selecting the type of yarn, a desired amount of atomization can be obtained even if the drive voltage fluctuates or the characteristics of the ultrasonic vibrator 14 slightly vary.
[0017]
Another reason that it is preferable to select the yarn as the liquid supply medium is that even if the yarn 16 is brought into direct contact with the atomizing action surface 13a at the tip of the vibrating vibrator, If it is 16, there is a point that it does not become a large load on the ultrasonic transducer 14. For example, when the liquid (L) is supplied to the atomizing action surface 13a of the ultrasonic vibrator 14 using a relatively hard liquid supply medium, if the contact force between the two is strong, the ultrasonic vibrator 14 is given. Since the load is large, the occurrence of vibration is suppressed. Conversely, if the two are slightly separated from each other, the supply of the liquid (L) stops, so that atomization cannot be performed. That is, if a relatively hard liquid supply medium is used, very fine position adjustment between the liquid supply medium and the atomizing surface 13a is required. However, when the yarn 16 is used as the liquid supply medium, the yarn 16 has a low stiffness, so that even when the yarn 16 comes into contact with the ultrasonic vibrator 14, the vibration characteristics are not affected. In addition, since the position adjustment between the yarn 16 and the atomizing action surface 13a can be relatively easily set, a high-precision atomization amount can be easily obtained by using the yarn.
[0018]
In the above-described embodiment, the case where the fiber bundle 16 is installed from below on the atomizing action surface 13a of the ultrasonic vibrator 14 is exemplified. However, the present invention is not limited to only the embodiment illustrated in FIG. For example, FIG. 3 is a diagram showing another embodiment of the present invention. In FIG. 3, (a) is an external perspective view of an ultrasonic atomizer according to another embodiment, and (b1) is a top view for explaining the structure of the ultrasonic atomizer. (B2) is a diagram illustrating another example of the ultrasonic atomizer shown in (b1).
[0019]
According to the ultrasonic atomizer in another embodiment illustrated in FIG. 3, the liquid (L) is supplied by wrapping the fiber bundle 16 right and left over the atomizing action surface 13 a of the ultrasonic vibrator 14. It is also possible to supply. This embodiment is suitable, for example, when the ultrasonic vibrator 14 is attached to the tip of the bottle 30. The liquid (L) in the bottle 30 is supplied to the upper portion of the bottle 30 by a liquid supply medium such as a sponge 31 installed in the bottle 30. The fiber bundle (thread) 16 is in contact with the tip of the sponge 31, and is supplied with the liquid (L). Since the fiber bundle (yarn) 16 is covered by the pipe 17 from the tip of the sponge 31 to the atomizing surface 13a, the evaporation of the liquid (L) is prevented, and the liquid (L) is efficiently discharged. Supply can be planned. Note that (b1) illustrates a case where one fiber bundle (yarn) 16 is stretched over, and (b2) further illustrates one fiber bundle (yarn) 16 as compared with the case of (b1). Is added. As described above, by changing the number, type, and the like of the fiber bundles (yarns) 16, it is possible to obtain a desired amount of atomization.
[0020]
Specifically, in the ultrasonic atomizer shown in FIG. 1, a 400 kHz ultrasonic vibrator 14 and a fiber bundle 16 using a three-twisted cotton thread of 20th count and having a diameter of 12 μm or less are used. When the amount of atomization per hour was set to 0.06 to 2.2 g with the atomized particle size of, the variation in the amount of atomization could be suppressed to about ± 12%. Unlike the case where a sponge is used as a liquid supply medium for an ultrasonic vibrator as described in the related art, a fiber bundle (yarn) 16 is used to realize the atomization amount under such severe conditions. This is because the. In the case of the fiber bundle (yarn) 16, the liquid (L) can be efficiently supplied to the ultrasonic vibrator 14, so that atomization can be performed under the conditions shown in the above embodiment. It is.
[0021]
Further, in the ultrasonic atomizer according to the present embodiment, by devising a structure for supplying electric power to the ultrasonic vibrator 14, the ultrasonic atomizer can reduce the manufacturing cost and realize the compactness. It is possible to provide. 4A is a diagram showing a structure of an ultrasonic atomizer according to the present invention, and FIG. 4B is a diagram showing a structure of a conventional ultrasonic atomizer.
[0022]
In the conventional ultrasonic atomizer shown in FIG. 4B, the ultrasonic vibrator 14, the drive circuit 10, and the power supply 11 are connected by two signal lines 41, respectively, and a total of four signal lines 41 Was needed. However, as shown in FIG. 4A, in the ultrasonic atomizer according to the present invention, the support 40 of the ultrasonic vibrator 14 is made of metal, and the power of the ultrasonic vibrator 14 is obtained from the support 40. Structured. That is, since the power supply 11 was directly connected to the support 40 and the drive circuit 10, the number of signal lines 41 could be reduced from four to one. As a result, the size of the ultrasonic atomizer itself can be reduced, and as a result, the manufacturing cost can be reduced.
[0023]
【The invention's effect】
As described above, according to the present invention, even if the driving voltage of the circuit and the characteristics of the vibrator slightly vary, it is possible to secure a substantially constant amount of atomization, and it is possible to manufacture the ultrasonic wave at low cost. An atomizer can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a schematic configuration of an ultrasonic atomizer according to the present embodiment.
FIG. 2 is a diagram for explaining a relationship between a yarn type and a liquid transmission amount.
FIG. 3A is an external perspective view of an ultrasonic atomizer according to another embodiment, and FIG. 3B is a top view for explaining the structure of the ultrasonic atomizer. (B2) is a diagram illustrating another example of the ultrasonic atomizer shown in (b1).
FIG. 4A is a diagram illustrating a structure of an ultrasonic atomizer according to the present invention, and FIG. 4B is a diagram illustrating a structure of a conventional ultrasonic atomizer.
[Explanation of symbols]
Reference Signs List 10 drive circuit, 11 power supply, 12 piezoelectric element, 13 ultrasonic horn, 13a atomizing surface, 14 ultrasonic vibrator, 15 spray liquid tank, 16 fiber bundle (thread), 17 pipe, 30 bottle, 31 sponge, 40 Support, 41 signal line.

Claims (4)

The liquid supplied from the fiber bundle is atomized by the ultrasonic oscillator by capillary action by arranging the fiber bundle drawn out of the container containing the liquid on the atomizing action side of the ultrasonic oscillator. And ultrasonic atomizer. The ultrasonic atomizer according to claim 1,
The ultrasonic atomizer, wherein the fiber bundle is arranged at a position deviated from the vicinity of the center of the atomizing action surface of the ultrasonic transducer. The ultrasonic atomizer according to claim 1 or 2,
The said fiber bundle is a thread | yarn, The ultrasonic atomizer characterized by the above-mentioned. The ultrasonic atomizer according to any one of claims 1 to 3,
An ultrasonic atomizer, wherein a support of the ultrasonic vibrator is made of metal, and electric power of the ultrasonic vibrator is obtained from the support.

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