JPH04118070A - Ultrasonic atomizer - Google Patents

Abstract

PURPOSE:To reduce the power loss in a vibration system by providing a cylinder, a vibrator phone fixed in the cylinder, an electroacoustic transducer element for imparting ultrasonic vibration to the phone, an atomization part formed at the tip of the phone and a sleeve member for supplying a liq. to the atomization part to the atomizer. CONSTITUTION:This ultrasonic atomizer 1 is composed of a cylinder 2, a vibrator phone 3 fixed and supported in the cylinder 2, an electroacoustic transducer element 4 for imparting ultrasonic vibration to the phone 3 and a sleeve member 6 to be screwed on the cylinder 2. An annular liq. supply passage 7 is formed between the cylinder 2 and the sleeve member 6, and a liq. is supplied to the passage 7 from a liq. supply pipe 8 welded to the sleeve member 6. An atomization part 3a is formed at the tip of the phone 3. An annular nozzle 7a is formed between the cylinder 2 and the sleeve member 6, and the liq. is supplied to the atomization part 3a from the nozzle 7a and atomized. As a result, the phone is easily machined and assembled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention generally relates to a liquid substance such as a liquid fuel that is supplied (in this specification, liquid substance refers to a liquid such as a liquid fuel, or Regarding ultrasonic atomization devices for atomizing liquid substances such as cloudy solutions using ultrasonic vibration, in particular Ultrasonic atomizers applied to internal combustion engines used in drive devices of heat pump devices for power plants, etc. (b) Fuel injection nozzles for gas turbines, (c) Boilers and heating for industrial, commercial and domestic use Furnaces, heating burners, (d) Industrial liquid sprayers, such as drying sprayers for drying liquid materials such as food, pharmaceuticals, agricultural chemicals, fertilizers, etc., temperature and humidity control sprays, baked powder sprayers (ceramic) The present invention relates to an ultrasonic atomizer suitable for use in (e) non-industrial liquid sprayers, such as pesticide sprayers, disinfectant sprayers, etc.

[Prior Art] Conventionally, as an ultrasonic atomization device that atomizes a liquid substance into extremely small droplet size using ultrasonic waves, for example, Japanese Patent Application Laid-Open No.
As shown in Publication No. 13Ei2B2, a vibrator horn is disposed inside a cylinder, a sleeve member is disposed around the outer periphery of the cylinder, and a vibrator is connected to an annular liquid supply path formed between the cylinder and the sleeve member. A system is known in which the liquid is uniformly atomized by supplying liquid to the entire circumference of the atomizing surface at the tip of the horn.

Conventionally, in the above method, a fixing flange is formed integrally with the node portion of the vibrator horn, and the flange is fixed and supported on the cylinder.

[Problems to be Solved by the Invention] Theoretically, there is a point in the node portion of the vibration system of the vibrator horn that no power loss occurs even if it is fixed. However, in reality, because the fixing flange has a width rather than a point, and because the speed of sound differs even with the same material, the positions of the respective node parts are different even if the vibrator horn is manufactured with the same dimensions. It will be different. As a result, vibration occurs in the flange portion, which causes power loss in the vibration system.

Further, there are problems in that the cutting process of the flange requires high precision, which increases the cost, and that the flange needs to be tightened uniformly, resulting in poor assembly performance.

Furthermore, in an atomizing device, the relative position of the branch supply nozzle and the vibrator horn tip foil part is an important factor in atomizing characteristics, but in the case of fixation with a flange, the relative position is fixed. Therefore, there is a problem in that the degree of freedom in adjusting the atomization characteristics is restricted.

In order to solve these problems, the applicant has
No. 22894 discloses a cylinder, a vibrator horn fixed in the cylinder, an electric/acoustic transducer that imparts ultrasonic vibration to the vibrator horn, and an atomization formed at the tip of the vibrator horn. The present invention has proposed an ultrasonic atomizing device comprising a sleeve member for supplying liquid to the atomizing portion, and the vibrator horn is fixed by rubber members at both ends of the cylinder.

However, when the present inventor conducted various experiments,
It was found that cavitation caused bubbles to accumulate in the nozzle facing the vibrator horn, causing dripping and discontinuous spraying.

The present invention solves the above problems, and is an ultrasonic atomizer that reduces power loss in the vibration system, is easy to manufacture and assemble, and can prevent air bubbles from accumulating due to cavitation. The purpose is to provide

[Means for solving the problem] For this purpose, the ultrasonic atomization device of the present invention includes a cylinder 2,
A vibrator horn 3 fixed in the cylinder 2, an electro-acoustic transducer 4 for imparting ultrasonic vibration to the vibrator horn 3, and an atomizing portion 3a formed at the tip of the vibrator horn 3. , the atomizing section 3 is screwed onto the outer periphery of the cylinder 2.
a sleeve member 6 for supplying liquid, and the vibrator horn 3 is connected to rubber members 12 and 13 at both ends of the cylinder 2.
Further, the tip of the sleeve member 6 is located 0 to 1 mm behind the tip of the cylinder 2.

Note that the numbers added to the above configurations are for comparison with the drawings, and the configurations of the present invention are not limited thereby.

[Operation] In the present invention, since the vibrator horn is fixed and supported by rubber members at two locations on the cylinder, the vibrator horn is fixed to the cylinder with flexibility at a position that optimizes the atomization characteristics. It can be supported. In addition, since the tip of the sleeve member is located 0 to 1+u+ backward from the tip of the cylinder, the nozzle part is in an open state, cavitation does not occur, and dripping and discontinuity of spray can be prevented.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial cross-sectional view showing one embodiment of the ultrasonic atomization device of the present invention, and FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG.

As shown in FIGS. 1 and 2, the ultrasonic atomizer 1 includes a cylinder 2, a vibrator horn 3 fixed and supported within the cylinder 2, and an ultrasonic vibration applied to the vibrator horn 3. It is composed of an electric/acoustic transducer element 4 and a sleeve member 6 that is screwed onto the outer periphery of the cylinder 2 at a threaded portion 5 . An annular liquid supply path 7 is provided between the cylinder 2 and the sleeve member 6.
A liquid supply pipe 8 is formed and fixed to the sleeve member 6 by welding.
A liquid is supplied from the liquid supply path 7 to the liquid supply path 7 .

An atomizing section 3a is formed at the tip of the vibrator horn 3. The shape of this atomizing portion 3a is such that a radius of curvature is formed at the tip of a rod shape. Further, an annular nozzle part 7a is formed between the cylinder 2 and the sleeve member 6, and liquid is supplied from the nozzle part 7a to the atomizing part 3a and atomized into fine droplets by ultrasonic vibration.

The vibrator horn 3 is fixed and supported at both ends of the cylinder 2 by oil-resistant rubber members 12 and 13.

When fixing, first place the vibrator horn 3 inside the cylinder 2.
is inserted and positioned using a jig or the like so that their concentricity is adjusted and the relative position of the atomizing part 3a and nozzle part 7a is in the optimum atomizing state, and then liquid rubber is injected into both ends. It is to be fixed in place.

Therefore, machining of the O-ring and the O-ring groove is not necessary, improving dimensional accuracy and reducing costs.

In addition, since the concentricity between the vibrator horn 3 and the cylinder 2 is ensured, the sleeve member 6 is fixed to the cylinder 2 only by the short threaded part 5, and unlike the conventional case, the sleeve member 6 is fixed to the cylinder 2 by the short threaded part 5. There is no need for a fitting part to ensure concentricity between the two, making it possible to shorten the overall length and increase rigidity.

Furthermore, thermal strain caused by welding when fixing the liquid supply pipe 8 to the sleeve member 6 can be reduced.

FIG. 3 shows a method of fixing between the atomizing section side end of the vibrator horn 3 and the cylinder 2 using a rubber member 12. (a) shows a method in which the tip of the cylinder 2 is thickened, and the inner periphery of the tip of the cylinder 2 and the cylinder 2 are thickened. The rubber member 12 is arranged in the thick part, and (b) shows an example in which the tip of the cylinder 2 has a sharp edge.

FIG. 4 shows a method of fixing the end of the vibrator horn 3 opposite to the atomizing part and the cylinder 2 with a rubber member 13.
(a) is an example in which the rear end of 7 cylinders 2 is at a right angle; (b) is an example in which a stepped portion is formed on the inner circumferential side of the rear end of cylinder 2; (C) is an example in which a slope is formed on the inner circumferential side of the rear end of cylinder 2. This shows an example of forming a .

Next, features of the present invention will be explained with reference to FIGS. 5 and 6. FIG. 5 is an enlarged cross-sectional view of the nozzle portion for explaining the generation of cavity chiron, and FIG. 6 is an enlarged cross-sectional view of the nozzle portion showing one embodiment of the present invention.

As shown in FIG. 5, in a structure in which the tip of the sleeve member 6 is located forward of the tip of the cylinder 2 and the nozzle portion 7a contacts the vibrator horn 3, the nozzle portion 7a contacts the vibrator horn 3. Air bubbles accumulate in the area and create cavities. In particular, when the liquid flow rate decreases, the flow rate slows down, and the flow rate becomes unstable when the accumulated bubbles exit to the outside.

Therefore, in the present invention, as shown in FIG.
It is positioned 1 mm backward. Therefore, the portion of the nozzle portion 7a that contacts the vibrator horn 3 is open, preventing air bubbles from accumulating, and preventing dripping and discontinuous spraying.

[Effects of the Invention] As described above, according to the present invention, since the vibrator horn is fixed and supported by the rubber member at 211 locations on the cylinder, the vibrator horn is fixed to the cylinder at a position that optimizes the atomization characteristics. Compared to the conventional case of rigidly fixing with a flange, the power loss of the vibration system can be reduced to about half, and the cutting and assembly of the vibrator horn can be easily performed.

Also, make sure that the tip of the sleeve member is 0 to 1 points from the tip of the cylinder.
Since it is positioned 1 mm backward, air bubbles caused by the cavity can be prevented from accumulating, and dripping and discontinuous spraying can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view showing one embodiment of the ultrasonic atomization device of the present invention, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG.
The figure is an enlarged sectional view showing a method of fixing between the atomizing part side end of the vibrator horn and the cylinder with a rubber member, and FIG. FIG. 5 is an enlarged sectional view of the nozzle portion to explain the occurrence of cavitation, and FIG. 6 is an enlarged sectional view of the nozzle portion showing one embodiment of the present invention. 1... Ultrasonic atomizer, 2... Ninda, 3...
Vibrator horn, 3a... Atomization section, 4... Electric/acoustic conversion element, 6... Sleeve member, 7... Liquid supply path,
7a... Nozzle part, 12.13... Rubber member. Applicant Tonen Co., Ltd. Patent Attorney Hiroki Shirai (7 others) Figure 1 Figure 2 7 Shu AK Road Figure 3 (a) (b) (a) (b) (C) a

Claims (1)

[Claims] (1) A cylinder, a vibrator horn fixed in the cylinder, an electric/acoustic transducer that applies ultrasonic vibration to the vibrator horn, and an atomizer formed at the tip of the vibrator horn. , a sleeve member screwed onto the outer periphery of the cylinder to supply liquid to the atomizing section, the vibrator horn being fixed by rubber members at both ends of the cylinder, and a tip of the sleeve member; An ultrasonic atomization device characterized by being located 0 to 1 mm behind the tip of a cylinder.