JP2735325B2 - Ultrasonic atomizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICATION The present invention generally relates to a liquid substance such as a supplied liquid fuel (in the present specification, the liquid substance means not only a liquid such as a liquid fuel, but also a liquid substance). Ultrasonic atomizer utilizing ultrasonic vibrations, including, but not limited to, liquid substances such as turbid solutions, and more particularly to (1) automobiles, outboard motors, portable power units, An ultrasonic atomizer applied to an internal combustion engine used for a drive unit of a consumer heat pump device, (2) a fuel injection nozzle for a gas turbine, (3) an industrial, commercial and household boiler, a heating furnace, Heating burners, (4) industrial liquid sprayers, such as drying sprayers for drying liquid substances such as foods, pharmaceuticals, agricultural chemicals, and fertilizers, temperature control, humidity control sprays, and powdering sprayers (ceramic granulation) ), Spray coating equipment, reaction accelerator, and (5) Liquid sprayer other than for work,
For example, the present invention relates to an ultrasonic atomizer suitably used for an agricultural chemical sprayer, a disinfectant sprayer, and the like.

[Conventional technology]

Heretofore, in the case of an internal combustion engine such as a gasoline engine and a diesel engine, or a combustion device such as a boiler and a fan heater, when the supplied liquid fuel is burned, this liquid fuel is extremely reduced from the viewpoint of combustion performance. It is desirable to supply by atomizing to a small droplet diameter.

Conventionally, as such an apparatus for atomizing liquid fuel into an extremely small droplet diameter, an ultrasonic atomizer for atomizing supplied liquid fuel by using ultrasonic waves is known.

In the ultrasonic atomization device of the combustion device, in order to ensure good atomization characteristics over a wide fuel supply range, a liquid thin film is formed on the atomization surface and the capillary wave is excited with the smallest possible amplitude It is essential to do. Various devices have been devised for this purpose.

FIG. 2 shows an ultrasonic atomizing apparatus of a type that supplies a liquid to the entire circumference of the atomizing surface. The ultrasonic atomizing apparatus includes an outer cylinder 111, an inner cylinder 112, a vibrator horn 113, and an electro-acoustic conversion element 114. And a fuel supply passage 115 is formed between the inner cylinder 112 and the outer cylinder 111.
Is supplied to the vibrator horn 113 from the annular nozzle portion 116 to atomize the fuel.

[Problems to be solved by the invention]

However, in the above conventional ultrasonic atomizing device, the atomizing surface of the vibrator horn 113 is formed to have a larger diameter toward the tip, and the annular nozzle portion 116 is arranged to face the same. Liquid is smoothly supplied to the atomization surface and can be atomized according to the amount of liquid supplied.Atomization is possible at the position of the minimum effective amplitude, and the droplet size becomes extremely small and the turndown ratio is set high. However, there is a problem that the spray angle of the liquid becomes too wide, and the spray is formed in the opposite direction, which limits the application.

The present invention solves the above-mentioned problems, and maintains the atomization characteristics and the turndown ratio by improving the tip shape of the vibrator horn, and has a narrower spray angle and a wider range of ultrasonic atomization for applications. It is intended to provide a device.

[Means for solving the problem]

For this purpose, the ultrasonic atomizer of the present invention uses the vibrator body 3
And an outer cylinder 2 supported by the vibrator main body 3 via, for example, an O-ring, and a liquid storage portion 6 formed between a lower portion of the vibrator main body 3 and the outer cylinder 2. A vibrator horn 3a having a convex continuous curved shape is integrally formed at a tip of the main body 3, and an annular nozzle portion 2a is formed at a tip of the outer cylinder 2. The outer horn 3a is attached to the vibrator horn 3a. The nozzle portion 2a of the cylinder 2 is provided with a slight gap.

The numbers added to the above configuration are for comparison with the drawings for easy understanding, and do not limit the configuration of the present invention.

[Operation] In the present invention, for example, as shown in FIG. 1, the liquid supplied from the liquid supply pipe 7 reaches the vibrator horn 3a from the nozzle part 2a through the liquid storage part 6, and is subjected to ultrasonic waves. Atomized by vibration. At this time, since the liquid sprayed from the nozzle portion 2a flows smoothly along the vibrator horn 3a having a spherical shape, it becomes possible to atomize at the position of the minimum effective amplitude that can be atomized according to the liquid supply amount, The atomization characteristics can be improved, and the spray angle can be narrowed based on the turndown ratio.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partial sectional view showing one embodiment of the ultrasonic atomizing device of the present invention.

The ultrasonic atomizing device 1 includes an outer cylinder 2, a vibrator main body 3, and an electro-acoustic conversion element 4. The outer cylinder 2 is inserted into the vibrator main body 3 via an O-ring 5,
A liquid storage part 6 is formed between a lower part of the vibrator main body 3 and the outer cylinder 2. The liquid storage section 6 penetrates the outer cylinder 2 and is connected to a liquid supply pipe 7.

A vibrator horn 3a having a convex continuous curved shape is integrally formed at a tip of the vibrator main body 3, and an annular nozzle portion 2a is formed at a tip of the outer cylinder 2. The vibrator horn 3a The nozzle portion 2a of the outer cylinder 2 is disposed with a slight gap. Reference numeral 9 denotes a mounting screw hole.

Then, the liquid supplied from the liquid supply pipe 7 reaches the vibrator horn 3a from the annular nozzle portion 2a through the liquid storage portion 6, and here, by the ultrasonic vibration excited by the electro-acoustic transducer 4, Atomized. At this time, the nozzle
Since the liquid sprayed from 2a flows smoothly along the vibrator horn 3a having a convex continuous curved shape, it is necessary to narrow the spray angle without impairing the atomization characteristics even if the supply flow rate of the liquid increases. Can be.

〔The invention's effect〕

As described above, according to the ultrasonic atomizing device of the present invention, by improving the tip shape of the vibrator horn, the atomization characteristics can be improved, and a high turndown ratio can be obtained. The spray angle can be reduced.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing one embodiment of the ultrasonic atomizer of the present invention, and FIG. 2 is a schematic cross-sectional view showing one example of a conventional ultrasonic atomizer. 1 ... Ultrasonic atomizer, 2 ... Outer cylinder, 2a ...
... Annular nozzle part, 3 ... vibrator body, 3a ... vibrator horn, 6 ... liquid storage part, 7 ... liquid supply pipe.

Claims (1)

(57) [Claims] A vibrator main body, an outer cylinder supported by the vibrator main body, and a liquid storage portion formed between a lower portion of the vibrator main body and the outer cylinder. A vibrator horn having a convex continuous curved shape is integrally formed at the tip, and an annular nozzle portion is formed at a tip of the outer cylinder. The nozzle horn is slightly spaced from the vibrator horn. An ultrasonic atomizer, which is provided with: