JPH0545407Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to an ultrasonic atomizer that uses ultrasonic vibrations of a piezoelectric element to suck up and atomize liquid. The present invention relates to an improvement in the structure of an ultrasonic atomization device.

(Summary of the invention) The present invention is an ultrasonic atomizer in which a piezoelectric element is tightened and integrated with a shaft body having a liquid suction hole, and the upper end of the upper horn part of the shaft body has a net-like, porous or fiber structure. At least one of the shaped members is provided to make the atomized particles uniform.

(Prior Art) The present applicant has proposed an ultrasonic pump that pumps up and atomizes liquid by utilizing the structure of a bolted vibrator in Japanese Patent Application No. 309113/1983. This special request 1986
The structure of the ultrasonic pump of No.-309113 is shown in Figure 5.

In this Fig. 5, the shaft body 1 has an amplitude expanding horn part for the pump function (a horn part for pumping liquid) at the bottom.
4 and a disc-shaped part 5, and is also provided with a large amplitude-enlarging horn part (atomization horn part) 30 and a disc-shaped part 31 for the atomization function on the upper part. Shaft 1
The middle part is bolt-shaped and has male screw parts 2 and 3 formed therein. Further, a liquid suction through hole 6 is formed on the central axis of the shaft body 1, and the lower opening of this liquid suction through hole 6 is formed on the lower end surface of the shaft body 1 (i.e., the lower end surface of the disc-shaped portion 5). Located in the center, the upper opening is located on the upper end surface of the shaft body 1 (i.e., the disc-shaped portion 3
1) is located in the center of

Then, a disc-shaped flange 8 serving as a support part, a disc-shaped electrode plate 9A, a disc-shaped piezoelectric element 10A, a disc-shaped electrode plate 9B, a disc-shaped piezoelectric element 10B, a disc-shaped electrode plate 9C, a disc-shaped The piezoelectric element 10A is formed by inserting the shaft 1 into each of the through holes of the flat washer 12 and the disc spring 13, screwing the nuts 11A and 11B into the male threads 2 and 3 of the shaft 1, and tightening them. ，
Each member such as 10B is tightened and integrated with the shaft body 1. That is, the piezoelectric elements 10A, 10B and the shaft body 1
The relationship between the two is almost the same as that of a bolted vibrator.

In the ultrasonic pump that sucks up and atomizes liquid, when the liquid level P is within the range of the arrow Q and the lower part of the ultrasonic pump is immersed in liquid such as water, the electrode plate 9B and the electrode plates 9A, 9C When a high frequency voltage is applied between
The ultrasonic wave is magnified by the vibration amplifying horn part 4 at the lower part of the holder, and causes longitudinal vibrations of the ultrasonic waves (vibrations in the direction parallel to the axis as indicated by arrow R in FIG. 5) in the disc-shaped part 5 at the lower end. The longitudinal vibration of the disc-shaped portion 5 at the lower end of the shaft body is
This causes convection in the direction of blowing up the liquid suction through hole 6 as shown by arrow S, and at the same time, since liquids such as water have a property in which ultrasonic waves propagate more easily than air and have a high viscosity, the inside of the liquid suction through hole 6 The liquid moves upward through the through hole 6 due to the progress of the liquid in the upward direction of the ultrasonic vibration and the breathing action of the inner surface of the through hole 6 contracting. Further, the amplitude of the ultrasonic vibrations of the piezoelectric elements 10A and 10B is expanded by the amplitude expansion horn section 30, causing the disk-shaped section 31 to perform an expanded longitudinal vibration. As a result,
The liquid that has risen through the liquid suction through hole 6 is atomized by ultrasonic vibration of the upper end surface of the disc-shaped portion 31 where the upper opening is located, and becomes atomized particles (spray particles) and is dispersed into the atmosphere. do.

Figure 6 shows the relationship (curve Y; however, the input is 4W). From this figure, with the ultrasonic pump shown in Figure 5, the particle size of the atomized particles decreases in approximately inverse proportion to the driving frequency, and at 200kHz it is possible to atomize particles with a fine particle size of about 10μ, but the amount of atomization is quite small. It can be seen that at 20 to 30kHz, the amount of atomization is large, but the particle size becomes large, exceeding 30μ. (Problems to be solved by the invention) By the way, the ultrasonic pump with the basic structure shown in Figure 5 can be used to atomize and evaporate drain water from air conditioners and refrigerators, atomize liquid fuel, etc. However, in such a case, it is desirable that the particle size of the atomized particles be as small as possible so that the atomized particles can easily evaporate and vaporize, and also to reduce the variation in particle size. It is desired to reduce the amount. However, the basic structure shown in FIG. 5 has the following problems.

(1) The particle size of atomized particles depends on the driving frequency, and fine atomized particles and atomization efficiency are not compatible.

(2) At a driving frequency that provides good atomization efficiency, the particle size of atomized particles is 40 to 70μ, with large variations.

(3) Since the through holes 6 are directly open, it is inevitable that large diameter liquid particles will scatter or drip, and that secondary particle (secondary aggregation) phenomena will occur.

(4) If the input power to the piezoelectric element is increased or the amount of water is increased, water droplets will scatter.

(Means for Solving the Problems) In view of the above points, the present invention provides at least one of a net-like, porous, or fibrous member at the tip of the horn part where the upper opening of the through hole is located. Therefore, it is an object of the present invention to provide an ultrasonic atomization device that can obtain fine atomized particles and also prevent large-diameter liquid particles from scattering to make the atomized particles uniform.

In the present invention, a plurality of piezoelectric elements are tightened and integrated by a tightening means to a shaft body in which a through hole for liquid suction that opens at the upper and lower ends is formed in the axial direction, and the lower part of the shaft body is used as a horn part for pumping liquid. The upper part of the shaft body is a horn part for atomization, and at least one of a net-like, porous, or fibrous member is arranged at the upper end of the horn part for atomization so as to cover the opening of the through-hole and the periphery of the opening. By providing this, the above-mentioned conventional problems are solved.

(Function) In the ultrasonic atomizer of the present invention, since at least one of a net-like, porous, or fibrous member is provided at the tip of the horn part for atomizing liquid by ultrasonic waves, the shaft body The liquid that rises through the liquid suction hole due to the action of the liquid pumping horn at the bottom and overflows upward from the through hole forms a net with an extremely large surface area that undergoes ultrasonic vibrations along with the tip of the atomization horn. , it comes into contact with a porous or fibrous member and is atomized into fine particles by these. Moreover, since the large liquid particles that have flown out from the liquid suction holes come into contact with the net-like, porous or fibrous member and turn into fine particles, they are released from the outside of the net-like, porous or fibrous member. The atomized particles released are fine and uniform with little variation in particle size.

(Example) Hereinafter, an example of the ultrasonic atomization device according to the present invention will be described with reference to the drawings.

FIG. 1 shows the main structure of a first embodiment of the present invention. The structure below the amplitude expanding horn section 30 for liquid atomization, which is formed at the upper part of the shaft body 1, is the same as the basic ultrasonic pump described in FIG. 5 above.

In FIG. 1, the upper end of the horn portion 30 for liquid atomization is a disk-shaped portion 31A, and a conical recess 33 is formed on the upper surface of the disk-shaped portion 31A.
A through hole 6 for sucking up liquid is opened in the center of the conical recess 33 and extends through the shaft body 1 in the axial direction.
Further, a caulking piece 34 is integrally provided on the disc-shaped portion 31A. Then, using the caulking piece 34, a net-like or porous disk 35 made of metal, resin, etc. is arranged and fixed on the upper surface of the disk-shaped portion 31A. That is, by bending the caulking piece 34 inward, the net-like or porous disk 35 is attached to the horn portion 30.
It is attached so as to generate ultrasonic vibrations integrally with the disc-shaped portion 31A.

In the case of this first embodiment, the particle size of the atomized particles (spray particles) of liquid such as water is determined depending on the density or density of the net in the specified net-like or porous disk 35 or the porous pore size, and the size of the atomized particles (spray particles) of liquid such as water is determined. By using a precisely dense mesh and a porous material with a small pore size, fine atomized particles can be obtained regardless of the driving frequency.

FIG. 2 shows the main structure of a second embodiment of the present invention. The structure below the horn part 30 for liquid atomization formed at the upper part of the shaft body 1 is the same as that of the basic ultrasonic pump described in FIG. 5 above.

In FIG. 2, the upper end of the horn part 30 is a disc-shaped part 31A, and a conical recess 33 is formed on the upper surface of the disc-shaped part 31A. A through hole 6 is open. Then, the conical recess 33 on the upper surface of the disc-shaped part is attached by using the caulking piece 34 integrated with the disc-shaped part 31A.
A net-like or porous conical plate 36 made of metal, resin, etc. is arranged and fixed along.

In the case of this second embodiment, the basic operation is the same as that of the first embodiment described above, but a net-like or porous conical plate 36 is provided along the conical recess 33,
There is an advantage that the liquid such as water that has ascended through the liquid suction through-hole 6 is brought into contact with the conical plate 36 effectively.

FIG. 3 shows the main structure of a third embodiment of the present invention. The structure below the horn part 30 for liquid atomization formed at the upper part of the shaft body 1 is the same as that of the basic ultrasonic pump described in FIG. 5 above.

In FIG. 3, the upper end of the horn part 30 is a disc-shaped part 31A, and a conical recess 33 is formed on the upper surface of the disc-shaped part 31A. A through hole 6 is open. Then, the fibrous disk 37 and the net-like or porous disk 35 are arranged and fixed on the upper end surface of the disk-shaped portion 31A using the caulking piece 34 integrated with the disk-shaped portion 31A. That is, the mesh-like or porous disk 35 is stacked and arranged on the fibrous disk 37.

In the case of this third embodiment, the fibrous disk 37
Because of this arrangement, it is possible to obtain finer atomized particles more easily.

FIG. 4 shows the main structure of a fourth embodiment of the present invention. The structure below the horn part 30 for liquid atomization formed at the upper part of the shaft body 1 is the same as that of the basic ultrasonic pump described in FIG. 5 above.

In FIG. 4, the upper end of the horn part 30 is a disc-shaped part 31A, and a conical recess 33 is formed on the upper surface of the disc-shaped part 31A. A through hole 6 is open. Then, a net-like or porous hemispherical shell 39 with a fibrous member 38 provided inside the disc-shaped part 31A is attached to the disc-shaped part 31A by using a caulking piece 34 that is integrated with the disc-shaped part 31A.
It is placed and fixed on the upper end surface of 1A.

In the case of this fourth embodiment, finer atomized particles are obtained using the fibrous member 38, and the radiation area is increased by using the outer net-like or porous member as a hemispherical shell 39, so that the amount of atomized can be reduced. It is possible to increase the amount.

Note that it is also possible to provide multiple layers of net-like, porous, or fibrous members in various combinations.

(Effects of the Invention) As explained above, according to the ultrasonic atomization device of the present invention, a plurality of piezoelectric elements are fastened to a shaft body in which liquid suction holes are formed in the axial direction and open at the upper and lower ends. The lower part of the shaft body is used as a horn part for pumping liquid, the upper part of the shaft body is used as a horn part for atomization, and the upper end of the horn part for atomization has a net-like, porous or Since the structure is such that at least one of the fibrous members is provided so as to cover the opening of the through hole and the periphery of the opening, the following effects can be obtained.

(1) Atomized particles (spray particles) of liquid such as water are fine and homogeneous.

(2) Because the atomized particles are fine and homogeneous, secondary aggregation is less likely to occur.

(3) Radiation of water droplets can be reduced.

(4) By increasing the radiation area, the amount of atomization can be increased.

[Brief explanation of drawings]

FIG. 1 is a front sectional view of the main parts of the first embodiment of the ultrasonic atomization device according to the present invention, FIG. 2 is a front sectional view of the main parts of the second embodiment of the invention, and FIG. FIG. 4 is a front sectional view of the main part of the third embodiment of the present invention, FIG. 5 is a front sectional view of the main part of the fourth embodiment of the present invention, and FIG. FIG. 6 is a front cross-sectional view showing the basic configuration of the pump, and is a graph showing the relationship between the drive frequency, atomized particle size, and atomization amount in the ultrasonic pump of FIG. 5. 1... Shaft body, 2, 3... Male screw part, 4, 30...
...Amplitude expansion horn part, 5, 31, 31A...Disc-shaped part, 6...Through hole for liquid suction, 10A, 1
0B...Piezoelectric element, 11A, 11B...Nut,
33... Conical recess, 34... Caulking piece, 35...
... Reticular or porous disk, 36 ... Reticular or porous conical plate, 37 ... Fibrous disk, 38
... Fibrous member, 39 ... Net-like or porous hemispherical shell.

Claims (1)

[Claims for Utility Model Registration] (1) A plurality of piezoelectric elements are tightened and integrated by a tightening means to a shaft body having liquid suction holes opened in the upper and lower ends in the axial direction, and the lower part of the shaft body is lifted up. The upper part of the shaft body is used as a horn part for liquid, and the upper end of the atomizing horn part is provided with at least one of a net-like, porous, or fibrous member with the through-hole opening. and an ultrasonic atomization device, characterized in that it is provided so as to cover the periphery of the opening. (2) The upper end of the atomizing horn part is a disc-shaped part, and the upper surface of the disc-shaped part is formed with a conical recess with the liquid suction hole opening in the center. An ultrasonic atomization device according to claim 1 of patent registration.