JPH034957A - Ultrasonic atomizer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention generally relates to a liquid substance such as a supplied liquid fuel (in this specification, a liquid substance is not only a liquid such as a liquid fuel p, but also a liquid substance such as a liquid fuel p). The ultrasonic atomizer is used to atomize liquids (including liquids such as turbid solutions) using ultrasonic vibration, and is particularly applicable to (1) automobiles, outboard motors, portable power devices, Ultrasonic atomizers applied to internal combustion engines used in the drive devices of consumer heat pump devices, etc.; (2) fuel injection nozzles for gas turbines; (3) boilers and heating furnaces for industrial, commercial and domestic use; Heating burner, (4)
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 granulation), spray coating equipment, reaction acceleration and (5) an ultrasonic atomizer suitable for use in non-industrial liquid sprayers, such as pesticide sprayers, disinfectant sprayers, etc.

[Conventional technology]

Until now, in internal combustion engines such as gasoline engines and diesel engines, or external combustion engines such as boilers and fan heaters, when burning the supplied liquid fuel, from the viewpoint of combustion performance, the liquid fuel It is desirable to supply the liquid by atomizing it into extremely small droplet sizes. In particular, in internal combustion engines such as gasoline engines and diesel engines, in order to obtain favorable engine performance, the liquid substance injected into the intake pipe, that is, the liquid fuel, is atomized into extremely small droplet sizes and mixed with air. It is required to supply the combustion chamber of the engine.

Conventionally, as such a device for atomizing liquid fuel into extremely small droplet size, there has been known an ultrasonic atomization device that uses ultrasonic waves to atomize a supplied liquid. especially,
At this time, when the liquid fuel is required to be atomized over a wide flow rate range (high turndown), such as in a gasoline engine, a solenoid valve is used as the liquid fuel supply means, and an ultrasonic atomizer is used as the liquid fuel supply means. A method is adopted in which liquid fuel is supplied directly to the atomization surface of the atomization device.

In this type of ultrasonic atomizer, it is essential to form a thin film of liquid on the atomization surface in order to ensure good atomization efficiency over a wide fuel supply range. Various efforts have been made for this purpose.

FIG. 3 shows an ultrasonic atomizer that supplies liquid to the atomization surface from a plurality of holes, including a cylinder 1o1, a nozzle body 102,
It consists of a vibrator horn 1o3 and an electro-acoustic conversion element 104, a fuel supply passage 105 is formed in the cylinder 101, and an injection hole 106t communicating with the fuel supply passage 105 is formed in the nozzle body 102. A plurality of injection holes 106 are formed on the circumference of the nozzle body 102, and injection holes 10B
The injected fuel is supplied to the vibrator horn 103 to atomize the fuel.

FIG. 4 shows an ultrasonic atomizer that supplies liquid to the entire circumference of the atomizing surface, and is composed of an outer cylinder 111, an inner cylinder 112, a vibrator horn 113, and an electric/acoustic transducer 114. A fuel supply path 115 is formed between the cylinder txt and the inner cylinder 112, and fuel is supplied from the entire circumference of the outer cylinder 111 to the vibrator horn 1.
13 to atomize the fuel.

[Problem to be solved by the invention]

However, in the above conventional ultrasonic atomization device,
In either case, since a cylinder for supplying fuel is provided around the outer periphery of the vibrator horn, there is a problem in that the device becomes larger and heavier.

An object of the present invention is to solve the above-mentioned problems, and to reduce the size and weight of the device.

[Means to solve the problem]

For this purpose, the ultrasonic atomization device of the present invention includes an ultrasonic vibration generating means 2 for generating ultrasonic vibrations, a vibrator body 3 connected to the ultrasonic wave generating means, and a tip of the vibrator body. A vibrator horn 4 is formed, and a liquid supply path 3a is formed inside the vibrator main body 3. At the tip of the vibrator horn, there is an inclined surface portion 5b and a reduced diameter smaller than the inclined surface portion. A portion 5C is formed, and the liquid supply 3a is opened to the inclined surface portion 5b.

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

[Effect]

In the present invention, for example, as shown in the first example, the liquid supplied from the liquid supply pipe 5 is
The liquid that flows down to the atomization surface 4a of the vibrator horn 4 through the injection hole 3b and reaches the atomization surface 4a is atomized by ultrasonic vibration from the ultrasonic vibration generator 2.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. 1st
The figure is a sectional view showing an embodiment of the ultrasonic atomization device of the present invention.

In FIG. 1, an ultrasonic atomizer l is equipped with an ultrasonic vibration generator 2 for generating ultrasonic vibrations at its base, and a vibrator main body 3 is connected to the ultrasonic vibration generator 2. A vibrator horn 4 is formed at the tip of this vibrator body 3. The vibrator main body 3 is formed so that the diameter becomes larger toward the atomization surface 4a at the tip, but the diameter may be the same.

A liquid supply path 3a is formed in the axial direction inside the vibrator body 3, and a plurality of branch supply paths 3d are formed at one end of the liquid supply path 3a, and an injection hole 3b opens to the atomization surface 4a. A supply hole 3C is formed at the other end of the transducer main body 3 and opens at the side surface of the vibrator body 3, and a liquid supply pipe 5, which is fuel from a fuel injection valve (not shown), for example, is connected to the supply hole 3C. Fixed by welding.

At the tip of the vibrator horn 4, an enlarged diameter portion 5at, an inclined surface portion 5b, and a reduced diameter portion 5C are formed. Said enlarged diameter part 5
a. functions to increase the atomization area. One of the characteristics of the vibrator horn 4 in the present invention is that it is provided with an enlarged diameter portion 5a, but this is to ensure the effect of increasing the flow rate of the jetted liquid, and there is no need to ensure a large flow rate. In this case, there is no particular need to provide the enlarged diameter portion 5a, and there is no problem in using one having the same diameter. The angle γ of the reduced diameter portion 5C with respect to the axial center is from 0″ to 90″, preferably from 40″ to 5″.
0''. Figure 1(b) shows an example of γ=90',
(C) shows an example where γ=0°. The spray angle becomes wider as the angle γ becomes smaller, and becomes narrower as the angle γ becomes larger.

FIG. 1(d) shows another embodiment of the present invention, in which 5a after diameter reduction.
FIG. 1(e) shows still another embodiment of the present invention, in which the tip portion 4e of the vibrator horn 4 is cut to form an inclined surface portion. This is an example in which the curvature R is formed continuously in the reduced diameter portion.

The liquid supplied from the liquid supply pipe 5 passes through the liquid supply path 3at3cL and the injection hole 3b and reaches the atomization surface 4a of the vibrator horn 4, and the liquid that has reached the atomization surface 4a is subjected to ultrasonic vibration. It is atomized by ultrasonic vibration from the generator 2. The atomization surface 4a having such a configuration allows the atomized fuel droplets to be diffused in a wide angle direction, thereby improving the miscibility with air.

FIG. 2 shows another embodiment of the invention. In addition, the first
Components that are the same as those in the figures are given the same numbers, and their explanation will be omitted.

In the embodiment shown in FIG. 2, a shielding plate 6 is arranged opposite to the injection hole 3b, and a fixed piece 6a of the shielding plate 6 shown in FIG. 2(b) is fixed to the vibrator horn 4 by welding. In this embodiment, when the fuel flow rate supplied from the injection hole 3b increases and the liquid drips from the atomization surface 4a, the liquid substance is temporarily stopped by the shielding plate 6 and atomized there. Can prevent liquid dripping. Note that, as shown in Figure (C), a plurality of openings may be provided in the bottomed cylindrical shielding member 7, and the openings may be attached to the shielding member 7.

〔Effect of the invention〕

As explained above, according to the ultrasonic atomization device of the present invention, the passage for supplying the liquid substance to the atomization surface is
Since it is formed inside the vibrator body, it is lighter in weight and more compact than the conventional method in which the liquid supply passage is provided outside the vibrator body.

In addition, by improving the shape of the tip of the vibrator of the ultrasonic injection valve, the spray angle can be made appropriate regardless of the amount of fuel supplied, and the turndown ratio can be increased.

[Brief explanation of drawings]

FIGS. 1(a), (b), (C), (d), and (e) are sectional views of essential parts showing each embodiment of the ultrasonic injection valve of the present invention, and FIG. A schematic sectional view of another embodiment of the ultrasonic atomization device, FIGS. 2(b) and 2(c) are perspective views of the shielding member,
3 and 4 are schematic cross-sectional views showing an example of a conventional ultrasonic atomization device. 1... Ultrasonic atomization device, 2... Ultrasonic vibration generator,
3... Vibrator body, 3a... Liquid supply path, 4...
Vibrator horn, 4a... Atomization surface, 5... Liquid supply pipe, 5a... Expanded diameter part, 5b... Inclined surface part, 5c...
Reduced diameter portion, 6.7...shielding member.

Claims (2)

[Claims] (1) Ultrasonic generation means for generating ultrasonic vibrations;
The vibrator includes a vibrator body connected to the ultrasonic generating means, a vibrator horn formed at the tip of the vibrator body, and a liquid supply path formed inside the vibrator body. An ultrasonic atomization device characterized in that an inclined surface portion and a reduced diameter portion smaller in diameter than the inclined surface portion are formed at a tip of the horn, and the liquid supply path is opened in the inclined surface portion. (2) The ultrasonic atomization device according to claim 1, characterized in that a shielding member is disposed opposite to the opening of the liquid supply path, and the shielding member is fixed to the vibrator horn.