JPH0342067A - Ultrasonic injection valve - Google Patents

Abstract

PURPOSE:To always obtain an appropriate angle of spray and to obtain a uniform full-arc spray by forming an inclined-surface part and a contracting part having a smaller diameter than the inclined-surface part at the tip of a vibrator horn and opposing the opening of a sleeve to the inclined-surface part. CONSTITUTION:A vibrator horn 10 and a sleeve 9 for supplying fuel over the whole periphery of the horn 10 arranged on the periphery of the horn 10 are provided. A expanding part 10a, inclined-surface part 10b and contracting part 10c are formed at the tip of the horn 10. An opening 9c of the sleeve is opposed to the inclined-surface part 10b. Liq. fuel is passed through the whole periphery of a circumferential groove 5b and supplied to the whole peripheries of the opening 9c and inclined-surface part 10b. The fuel sent to the inclined-surface part 10b is atomized by the ultrasonic vibration caused by an ultrasonic vibration generating part 2, sent smoothly to the contracting part 10c, and fully atomized. Consequently, an angle alpha of spray is maintained.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an ultrasonic injection valve applied to internal combustion engines used in automobiles, outboard motors, portable power units, drive devices for consumer heat pump devices, etc. The present invention also relates to (0) fuel injection nozzles for gas turbines, (2) industrial, commercial and domestic boilers, heating furnaces, and heating burners, (3) industrial liquid sprayers, such as food and pharmaceutical products. , drying sprayers for drying liquid materials such as agricultural chemicals and powders, temperature control and humidity control sprays, baked powder sprayers (ceramic granulation), spray coating equipment, reaction accelerators, and (4) industry. Liquid sprayers other than those for
For example, the present invention relates to an ultrasonic injection valve suitable for use in pesticide sprayers, disinfectant sprayers, and the like.

[Prior Art] In internal combustion engines such as gasoline engines and diesel engines, when the supplied liquid fuel is combusted, it is necessary to atomize the liquid fuel into extremely small droplet sizes from the viewpoint of combustion performance and exhaust characteristics. It is desirable to mix it with air and supply it into the intake pipe. FIG. 4 shows a cross-sectional view of a spark ignition engine using an ultrasonic injection valve, in which 21 is a cylinder, 22 is a contorrad, 23 is a piston, 24 is a combustion chamber,
25 is an intake pipe, 2B is an intake valve, 27 is an exhaust pipe, and 28 is an exhaust valve. A mounting body 31 to which an ultrasonic atomizer 29 and a fuel injection valve 30 are fixed is arranged at a predetermined position of the intake pipe 25, and the ultrasonic atomizer! Vibrator 3 installed at the tip of 29
2 is arranged facing the intake valve 26. Then, fuel is supplied from the fuel supply path 33 of the fuel injection valve 30 to the vibrator 32, where the fuel is atomized and sprayed into the intake pipe 25.

Conventionally, ultrasonic injection valves for atomizing liquid fuel are
2. Description of the Related Art Ultrasonic injection valves that supply liquid to an atomizing surface from a plurality of holes and ultrasonic injection valves that supply liquid to an atomizing surface from all around the circumference are known.

FIG. 5 shows a multi-hole ultrasonic injection valve that supplies liquid to the atomizing surface from a plurality of holes, including a cylinder 101 and a nozzle body 10.
2. Consisting of a vibrator horn 103 and an electro-acoustic transducer 104, a fuel supply passage 105 is formed in the cylinder 101, and an injection hole lO6 communicating with the fuel supply passage 105 is formed in the nozzle body 102. There is. The injection hole 10B is
A plurality of injection holes 10 are formed on the circumference of the nozzle body 102.
The fuel injected from B is supplied to the vibrator horn 103 to atomize the fuel.

Furthermore, FIG. 6 shows an annular type ultrasonic injection valve that supplies liquid to the atomizing surface from a plurality of holes, and the outer cylinder 111
, an inner cylinder 112, a vibrator horn 113, an electric/acoustic transducer 114, and an outer cylinder 11.
A fuel supply path 115 is formed between the outer cylinder 111 and the inner cylinder 112, and fuel is supplied from the entire circumference of the outer cylinder 111 to the vibrator horn 113 to atomize the fuel.

[Problem to be solved by the invention]

By the way, in this type of ultrasonic injection valve, in order to ensure good atomization efficiency over a wide fuel supply range, it is essential to uniformly form a thin film of liquid on the atomization surface of the vibrator. . Furthermore, in order to atomize the entire amount of the supplied fuel, it is important that the supplied fuel is not blown away on the atomization surface even if the speed of the supplied fuel becomes high.

However, in the above-mentioned multi-hole ultrasonic injection valve, the amount of atomization is determined by the amount supplied from the injection hole 106, so the turndown ratio, which indicates the ratio between the maximum amount of atomization and the minimum amount of atomization, cannot be set large. , when placed horizontally, the injection hole 108
The problem is that it is difficult to distribute the liquid evenly, resulting in uneven spraying. Furthermore, there is a limit to increasing the number of injection holes 108 in order to uniformly distribute the fuel, and there is also the problem that machining of the injection holes 106 is difficult, increasing manufacturing costs.

Furthermore, in the annular type ultrasonic injection valve, the amount of atomization is determined by the clearance 116 between the tip of the outer cylinder 111 and the vibrator horn 113. The problem is that mounting accuracy is required, which increases manufacturing costs. Furthermore, if the accuracy of this clearance tte is low, there are problems in that a large turndown ratio cannot be obtained and the spray becomes non-uniform.

Furthermore, the conventional system described above has a problem in that the spray angle θ of the atomized fuel by the ultrasonic injection valve becomes large, and the fuel adheres to the inner wall of the intake pipe, which has a relatively small diameter.

An object of the present invention is to solve the above-mentioned problems and problems, and by improving the shape of the tip of the vibrator of an ultrasonic injection valve, it is possible to make the spray angle appropriate regardless of the amount of fuel supplied, and to It is an object of the present invention to provide an ultrasonic injection valve that has a large turndown ratio and can provide uniform spray all around the circumference.

[Means to solve the problem]

For this purpose, the ultrasonic injection valve of the present invention has a vibrator horn 10.
and a sleeper 8 disposed on the outer periphery of the tldB transducer horn 10 for supplying fuel over the entire circumference of the transducer horn 10. At the tip of the transducer horn 10, an enlarged diameter portion 10a1 and an inclined surface portion 10b are provided. and a reduced diameter portion 10c are formed, and an opening 9 of the sleeve is formed opposite to the inclined surface portion 1ob.
It is characterized by arranging c.

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.

[Effect]

In the present invention, for example, as shown in FIGS. 1 and 2, the liquid fuel passes through the circumferential groove 5b1, the passage 9a1, the inclined passage 9b, and the opening 9c, respectively, and reaches the atomization surface 4. . At that time, the liquid fuel passes through the entire circumference of the circumferential groove 5b and is supplied to the entire circumference of the opening 8c and the inclined surface section 10b, so that in the process, the liquid fuel is distributed with a generally uniform film thickness. and reaches the inclined surface portion 10b. The liquid fuel that has reached the inclined surface part 10b is atomized by the ultrasonic vibrations from the ultrasonic vibration generating part 2, and the fuel that cannot be atomized here smoothly flows to the reduced diameter part 10c where the entire amount is is atomized and sprayed at a spray angle α.

Although the matters explained above relate to ultrasonic atomization of fuel for internal combustion engines, the present invention is applicable to the technical fields as described above, and is therefore limited to ultrasonic injection valves applied to internal combustion engines. It is clear that it is not.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of essential parts showing one embodiment of the ultrasonic injection valve of the present invention, FIG. 2 is an overall sectional view showing one embodiment of the ultrasonic injection valve of the present invention, and FIG. It is a sectional view taken along the line ■-■.

2 and 3, the ultrasonic injection valve 1 of the present invention
is equipped with an ultrasonic vibration generating section 2 for emitting ultrasonic vibrations at the base, and this ultrasonic vibration generating section 2 includes a transducer shaft section 3.
and a vibrator horn 10 are connected, and an atomizing surface 4 is formed at the tip thereof.

A substantially annular sleep member 5 is disposed on the outer circumference of the vibrator shaft portion 3 so as to surround it, and the outer circumference of the tip portion 5a of the sleep member 5 has a diameter slightly larger than the outer diameter of the tip portion 5a. An annular casing member 6 having a large inner diameter is fixed,
A sleeve 9 is formed between the tip portion 5a of the sleeve member 5 and the casing member 6. Furthermore, the sleep member 5
The distal end portion of the casing member 6 is tapered, and therefore, there is an annular passage 9a1 between the outer circumferential surface of the distal end portion 5a of the sleep member 5 and the inner circumferential surface of the casing member e.
An inclined passage 9b and an opening 9c will be formed. The sleep member 5 is provided with a circumferential groove 5b at a suitable position on its outer peripheral surface over the entire circumference in the radial direction, and the casing member 8 is provided with a liquid fuel supply port 8 at a suitable position.
a is provided, and this liquid fuel supply port 6a communicates with the circumferential groove 5b and the passage 9a.

Liquid fuel is supplied from the fuel injection valve to the liquid fuel supply port 6a of the casing member 6, and the circumferential groove 5 of the sleep member 5
It is supplied over the entire circumference of b.

The liquid fuel supplied to the circumferential groove 5b passes through the passage 9as and the inclined passage 9b, reaches the opening 9c, and reaches the atomization surface 4. The liquid fuel that has reached the atomization surface 4 is atomized by ultrasonic vibrations from the ultrasonic vibration generator 2 .

FIG. 1 is a sectional view showing the shape of the tip of the sleeper 9 and the vibrator horn 10 of the ultrasonic injection valve 1. As shown in FIG. At the tip of the vibrator horn 10, an enlarged diameter portion 10a1 and an inclined surface portion 10b are provided.
and a reduced diameter portion 10c are formed. Said enlarged diameter part 10
a functions to increase the atomization area. The inclined surface portion 10b is formed at an angle β with respect to the axis of the vibrator 10, and the reduced diameter portion 10c is formed at an angle γ with respect to the axis of the vibrator 10. One of the features of the vibrator horn 10 of the present invention is that it is provided with an enlarged diameter portion 10a, but this is to ensure the effect of increasing the flow rate of the injected 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 10a, and there is no problem in providing the enlarged diameter portion 10a.

An example of the dimensions of each part is shown below. In addition, the vibrator horn 1
The diameter of the enlarged diameter part 10a of 0 is D: 9, the inclined surface part 10
Let the axial length of b be l: 0.5 mm. L/D is 1
/10 to 1/30, preferably about 1/18.

■The spray angle α is 300 to 45°. The reason for this is that when an engine is equipped with an ultrasonic injection valve, it is important to set the spray angle so that the fuel does not adhere to the inner wall of the intake pipe, but it is also necessary to set the spray angle to a certain extent to improve the mixing effect with the air. This is because.

(2) The angle β between the tip of the sleeper 9 and the inclined surface portion 10b is 5 to 45 degrees, preferably about 16 degrees, which is an angle at which the atomized fuel is not blown away and easily rides on the atomization surface.

■Angle γ of the reduced diameter portion 10c with respect to the axial center is 06 to 90
'', preferably 40'' to 50°. FIG. 1(b) shows an example where γ=90°, and FIG. 1(C) shows an example where γ=01. The spray angle α becomes wider as the angle γ becomes smaller, and the spray angle α becomes wider as the angle γ becomes smaller.
When becomes large, it works in the direction of narrowing.

■The upper and lower limits of the distance D1 between the opening 9c of the sleeper 9 and the enlarged diameter portion 10a of the vibrator horn 10 are 0.05■~
0°Smm, preferably 0. i-th~0.2l-(D+/D
=0.01~0.02). The reason is that below the lower limit, the distance between the tip of the sleeper 9 and the vibrator horn 10 is too narrow and there is a risk of them coming into contact;
When the flow rate and pressure of the liquid are low, the liquid drips without reaching the surface of the inclined surface portion 10b.

(2) The distance between the opening 9c of the sleeve 9 and the enlarged diameter portion 8a is 0-0.5 (L+/L=0 to 1). Distance L1
If the aperture 9C is made smaller and the opening 9C is moved toward the enlarged diameter portion 10a, it becomes difficult to form a liquid film, and if it is moved toward the reduced diameter portion 10c, the incident angle becomes negative and the liquid penetrates through.

FIG. 1(d) shows another embodiment of the present invention, in which the reduced diameter part 10
This is an example in which c has a two-stage structure 10c 10c'. Further, FIG. 1(e) shows still another embodiment of the present invention,
This is an example in which the tip portion 10e of the vibrator horn 10 is cut to form a curvature R continuous to the inclined surface portion and the reduced diameter portion.

The operation of the ultrasonic injection valve of the present invention having the above-described structure will be described below.

The liquid fuel is distributed through the circumferential groove 5c, the passage 9a1, and the inclined passage 9b.
, respectively, and reach the atomization surface 4 through the openings 9c. At this time, the liquid fuel passes through the entire circumference of the circumferential groove 5c and is supplied to the entire circumference of the opening 9c and the inclined surface portion 10b, so that in the process, the liquid fuel is distributed with a generally uniform film thickness. and reaches the inclined surface portion 10b. Inclined surface part 1
The liquid fuel that has reached 0b is atomized by the ultrasonic vibrations from the ultrasonic vibration generating section 2, and the fuel that cannot be atomized here smoothly flows to the reduced diameter section 10c where the entire amount is atomized. and will be sprayed at a spray angle α.

Note that the present invention is not limited to the above-mentioned embodiments, and various modifications can be made.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to improve the shape of the tip of the vibrator of an ultrasonic injection valve to make the spray angle appropriate regardless of the amount of supplied liquid, and to obtain a large turndown ratio. Uniform all-around spray is obtained.

In addition, when applied to internal combustion engines, the shape of the tip of the vibrator of the ultrasonic injection valve is improved, making it possible to optimize the spray angle regardless of the amount of supplied liquid, which allows the fuel to reach the inner wall of the intake pipe. It is possible to provide an ultrasonic injection valve that can supply fuel into a cylinder without adhesion, has a large turndown ratio, and can obtain uniform all-around spray, and can increase the spray flow rate. It is possible to operate the ultrasonic atomizer even during normal operation, and the vaporizer can be omitted, which simplifies the mechanism.

[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. An overall sectional view showing one embodiment of an injection valve,
FIG. 3 is a sectional view taken along the line ■-■ in FIG. 2, FIG. 4 is a sectional view of an engine to which the present invention is applied, and FIGS. 5 and 6 are sectional views of a conventional ultrasonic injection valve. be. 1... Ultrasonic injection valve, 9... Sleep, 10...
Vibrator horn, 10a... enlarged diameter part, 10b... inclined surface part, 10c... reduced diameter part.

Claims (2)

[Claims] (1) It has a vibrator horn and a sleeper disposed on the outer periphery of the vibrator horn for supplying fuel over the entire circumference of the vibrator horn, and the tip of the vibrator horn has an inclined surface portion and the inclined surface portion. An ultrasonic injection valve characterized in that a reduced diameter portion is formed with a smaller diameter than the surface portion, and a sleep opening is disposed opposite to the inclined surface portion. (2) The ultrasonic wave according to claim 1, wherein the tip of the vibrator horn is formed with an enlarged diameter part, a reduced diameter part smaller in diameter than the enlarged diameter part, and smaller in diameter than the inclined surface part. injection valve.