JPH05208152A - Ultrasonic atomizer - Google Patents

Abstract

(57) [Abstract] [Purpose] The power loss of the vibration system can be reduced, the manufacturing and the assembling can be easily performed, and the uniformity of the liquid supply distribution in the atomizing portion and the stability of the spray can be ensured. [Structure] A cylinder 2, a vibrator horn 3 fixed in the cylinder 2, an electro-acoustic conversion element 4 for imparting ultrasonic vibration to the vibrator horn 3, and fitted on the outer circumference of the cylinder 2. A sleeve member 5 that forms a liquid supply path 6 with the cylinder 2, an atomizing portion 3a formed at the tip of the vibrator horn 3, and the cylinder at the node portion on one side of the vibrator horn 3. 2 and an elastic body 9b provided between the cylinder 2 and the atomizing portion 3a side of the vibrator horn 3 and vibrated by the two elastic bodies 9a and 9b. The child horn 3 is fixed to the cylinder 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention includes a liquid substance such as a liquid fuel to be supplied (in the present specification, the liquid substance includes not only a liquid such as a liquid fuel but also a liquid substance such as a suspension solution). Ultrasonic atomization device for atomizing using ultrasonic vibration, especially for (a) automobiles, outboard motors, portable power devices, drive devices for consumer heat pump devices, etc. Ultrasonic atomizer applied to used internal combustion engine, (b) fuel injection nozzle for gas turbine, (c) industrial, commercial and domestic boiler, heating furnace, heating burner, (d) industrial Liquid atomizer, for example, a drying atomizer for the purpose of drying liquids such as foods, pharmaceuticals, pesticides, fertilizers,
Suitable for temperature control, humidity control spray, spray powder sprayer (ceramic granulation), spray coating device, reaction accelerator, and (e) non-industrial liquid sprayers, such as pesticide sprayers, disinfectant sprayers, etc. The present invention relates to an ultrasonic atomizing device used for.

[0002]

2. Description of the Related Art As an ultrasonic atomizer for atomizing a liquid substance into an extremely small droplet diameter by ultrasonic waves, for example, a vibrator horn is arranged in a cylinder and a sleeve member is fitted around the outer periphery of the cylinder. However, there is known a method of atomizing the liquid by supplying the liquid from the annular nozzle portion formed between the cylinder and the sleeve member to the entire circumference of the tip atomizing portion of the vibrator horn. In this method, conventionally, a method is generally used in which a fixing flange is integrally formed on a node portion (a portion that does not vibrate) on one side of a vibrator horn, and the flange is fixed and supported on a cylinder.

The node portion of the vibrator horn theoretically has a point that no power loss occurs even if it is fixed.
However, in reality, since the fixing flange has a width instead of a point, and the sound velocity is different even with the same material, as a result, the fixing flange vibrates, and the power loss of the vibration system is correspondingly increased. Has a problem that occurs. Further, there is a problem that accuracy is required for cutting the flange, resulting in high cost, and the assembling property is poor because the flange needs to be uniformly tightened.

Further, since the liquid penetrates between the cylinder and the vibrator horn, the startability is deteriorated, and bubbles are generated in the liquid by the ultrasonic vibration of the vibrator horn. There is a problem in that the stability of the spray is impaired as a result of being jetted from.

In order to solve the above problems, the present applicant has
In Japanese Unexamined Patent Publication No. 3-224654, an oscillator horn is fixed at two node portions by elastic bodies (O-rings), and the oscillator horn is fixed to a cylinder with flexibility.
By supporting it, the power loss of the vibration system is reduced, and by filling a sealing material made of oil-resistant liquid rubber or the like between the vibrator horn and the tip of the cylinder, It proposes an ultrasonic atomization device that can prevent the deterioration of the start-up and the generation of bubbles caused by the liquid entering the space between them and can ensure the stability of the spray.

[0006]

However, in the above-mentioned conventional ultrasonic atomizing device, since the tip portion of the vibrator horn is fixed by the sealing material, the power loss of the vibration system is large and the ultrasonic wave is generated. There is a problem that the durability of the sealing material is deteriorated by the vibration, the startability is deteriorated and bubbles are generated, and the stability of the spray cannot be secured.

The present invention solves the above-mentioned problems, reduces the power loss of the vibration system, can be easily manufactured and assembled, and has a uniform liquid supply distribution in the atomizing section. An object of the present invention is to provide an ultrasonic atomizing device that can ensure the stability of spraying.

[0008]

In order to achieve the above object, an ultrasonic atomizing device of the present invention comprises a cylinder 2, a vibrator horn 3 fixed in the cylinder 2, and a vibrator horn 3. Electro-acoustic conversion element 4 for applying ultrasonic vibration to the
A sleeve member 5 fitted to the outer periphery of the cylinder 2 to form a liquid supply path 6 between the cylinder 2 and the cylinder 2, an atomizing portion 3a formed at the tip of the vibrator horn 3, and the vibrator. At the node portion on one side of the horn 3, the cylinder 2
An elastic body 9a provided between the vibrator 9 and the elastic body 9a.
The elastic horn 3b is provided between the cylinder 2 and the atomizing section 3a, and the vibrator horn 3 is fixed to the cylinder 2 by the two elastic bodies 9a and 9b. It should be noted that the numbers added to the above-mentioned configurations are for comparison with the drawings for easy understanding, and the configurations of the present invention are not limited thereby.

[0009]

In the present invention, for example, as shown in FIG.
When the vibrator horn 3 is inserted into the cylinder 2, the vibrator horn 3 can be easily fixed and supported by the elastic bodies 9a and 9b, and the vibrator horn 3 and the cylinder 2 can be easily concentric. It will be. In addition, since the elastic body 9b exists between the vibrator horn 3 and the tip of the cylinder 2, it is possible to prevent the liquid from entering the space 10 between the two, and to prevent bubbles from being lost without impairing the startability. Can be prevented and the stability of spraying can be secured.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partial sectional view showing an embodiment of an ultrasonic atomizing device of the present invention, and FIG. 2 is a sectional view taken along the line AA of FIG.

The ultrasonic atomizer 1 includes a cylinder 2, a vibrator horn 3 fixed and supported in the cylinder 2, an electro-acoustic conversion element 4 for applying ultrasonic vibration to the vibrator horn 3, and a cylinder. The sleeve member 5 is fitted and press-fitted on the outer periphery of the sleeve 2. An annular liquid supply passage 6 is formed between the cylinder 2 and the sleeve member 5, and the liquid is supplied from the liquid supply pipe 7 to the liquid supply passage 6. The electro-acoustic conversion element 4 has electrodes 4 a and 4 b and is attached to the rear portion 3 b of the vibrator horn 3.

An atomizing portion 3a is formed at the tip of the vibrator horn 3. As the shape of the atomizing portion 3a, in addition to the hemispherical shape shown in the drawing, a rod-like shape with a rounded R at the tip edge portion, a diameter-expanding shape, a bat shape, or the like is adopted. The tip of the liquid supply path 6 is arranged above the atomizing section 3a, and the liquid is supplied from the liquid supply path 6 to the atomizing section 3a and atomized into fine droplets by ultrasonic vibration. As described above, since the liquid supply path 6 is formed between the cylinder 2 and the sleeve member 5 and is not affected by the vibration of the vibrator horn 3, the clearance thereof is made extremely small at about 0.05 to 0.1 mm. However, the spray amount does not become unstable.

A concave groove 3c is formed in a node portion (a portion which does not vibrate) in the rear portion 3b of the vibrator horn 3, and an elastic body 9a made of an O-ring is fitted in the concave groove 3c. Further, a concave groove is also formed at the tip of the cylinder 2, and an elastic body 9b made of an O-ring is fitted in the concave groove. Therefore, when the vibrator horn 3 is inserted into the cylinder 2,
The oscillator horn 3 can be easily fixed by the elastic bodies 9a and 9b,
It can be supported, and the concentricity of the vibrator horn 3 and the cylinder 2 can be easily obtained. In addition, since the elastic body 9b exists between the vibrator horn 3 and the tip of the cylinder 2, it is possible to prevent the liquid from entering the space 10 between the two, and to prevent bubbles from being lost without impairing the startability. It is possible to prevent the occurrence of and to ensure the stability of spraying.

Next, the experimental results of the present invention will be described.
Elastic body 9 composed of an O-ring for supporting the vibrator horn 3
Of the a and 9b, the elastic body 9b on the tip side of the vibrator horn 3 is in direct contact with the liquid and also in contact with the vibrating portion of the vibrator horn 3, so that the load on the O-ring itself is large, In addition, the influence on the vibrator horn 3 is large. Therefore, as an O-ring, Viton [Hs (hardness) = 5
0, 70], silicone (Hs = 50), pendant rubber (Hs = 70), and fluorosilicone (Hs = 50), an experiment was conducted using kerosene. Table 1 shows the influence of various O-ring materials on the vibration characteristics, and each numerical value shows an average value.

[0015]

[Table 1]

As a result of the above, Viton (Hs = 50, 7
It can be seen that 0) has a resonance admittance lower than 1 at any hardness, and is in a state of being less likely to vibrate than other materials. Also, in terms of no-load output and current consumption, the pendant rubber is larger than other materials, and it can be seen that power consumption during use is large. Furthermore, comparing the current consumption in the initial state with that in the sprayed state, the value decreased when sprayed with Viton and pendant rubber, and the load decreased, whereas conversely with Silicon, the current consumption during spraying was higher. It can be seen that the load is increasing. It is considered that this is because silicon swells with kerosene.

Table 2 shows the influence of various O-ring materials on the spraying performance by relative evaluation.

[0018]

[Table 2]

As a result, Viton has problems in startability and durability, and in Silicon, heat generation, sealability, oil resistance,
It was found that there are problems in durability and current consumption, and that pendant rubber and fluorosilicone have problems in heat generation and current consumption. However, the startability, oil resistance, and durability are
It has been found that the pendant rubber and fluorosilicone are the most practical in view of the above-mentioned other excellent performances, although the ultrasonic atomization device has the minimum required specifications, and although there are some problems in current consumption and heat generation.

[0020]

As is apparent from the above description, according to the present invention, compared to the conventional example, the tip of the vibrator horn is not fixed, and the support portion of the vibrator horn is provided at three positions. Since it is possible to reduce the number of parts, it is possible to reduce the power loss of the vibration system and to easily manufacture and assemble.

Further, in order to prevent liquid from entering between the vibrator horn and the tip of the cylinder due to the elastic body,
Durability is significantly improved compared to conventional fixing with a seal material, and bubble generation is prevented and the uniformity of liquid supply distribution to the atomization surface and the stability of spraying are ensured without impairing the startability. be able to.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing an embodiment of an ultrasonic atomizing device of the present invention.

2 is a sectional view taken along the line AA of FIG. 1 and viewed in the direction of the arrow.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Ultrasonic atomization device, 2 ... Cylinder, 3 ... Transducer horn, 3a ... Atomization part 4 ... Electric / acoustic conversion element, 5 ... Sleeve member, 6 ... Liquid supply path 9a, 9b ... Elastic body

Claims (1)

[Claims] 1. A cylinder, a vibrator horn fixed in the cylinder, an electro-acoustic conversion element for applying ultrasonic vibration to the vibrator horn, and the cylinder fitted to the outer periphery of the cylinder. A sleeve member that forms a liquid supply path therebetween, an atomizing portion that is formed at the tip of the vibrator horn, and an elastic body that is provided between the cylinder at the node portion on one side of the vibrator horn, An ultrasonic atomization device, comprising: an elastic body provided between the cylinder and the cylinder on the atomizing portion side of the vibrator horn, and the vibrator horn is fixed to the cylinder by the two elastic bodies.