JPH01125554A - fuel atomization device - 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 relates to a fuel which is disposed in, for example, an intake pipe of an automobile and is used to atomize fuel injected from an injection valve into an intake passage. Regarding an atomization device.

(Prior art) Generally, in Japanese Patent Application Laid-Open No. 61-192845, etc.
An oscillation element that generates ultrasonic vibrations, a horn provided on one side of the oscillation element to amplify the ultrasonic vibrations of the oscillation element, and a vibration balancer provided on the other side of the oscillation element with respect to the horn. a oscillator provided at the tip of the horn to promote atomization of fuel injected into the intake passage from the injection valve; and a base of the horn for positioning the oscillator in the intake passage. Fuel atomization devices are known which consist of end-mounted mounting brackets.

In this type of fuel atomization device, a vibrator is disposed in the intake passage so as to face the injection valve, and the ultrasonic vibration of the vibrator causes atomization ('N conversion) of the fuel injected from the injection valve. By further promoting this, the fuel is mixed uniformly with the intake air, thereby improving the combustion efficiency of the engine.

(Problems to be Solved by the Invention) Incidentally, in the fuel atomization device, the higher the frequency of the ultrasonic vibrations generated by the oscillation element, the more atomization of the fuel is promoted in accordance with the frequency. or known.

However, with the above-mentioned conventional technology, there is a problem that when the oscillation frequency is increased, the amount of heat generated by the ultrasonic vibration increases, the characteristics of the oscillation element change, and the life span is shortened, so that the oscillation frequency cannot be increased that much.

Additionally, if there is an L-shaped bend in the middle of the intake passage, even if the fuel is atomized upstream of the bend, the fuel will adhere to the inner wall of the bend as a wall film flow. There is a problem in that this wall film flow becomes large droplets that are sucked into the cylinder together with the intake air, causing incomplete combustion.

The present invention was made in view of the problems of the prior art described above. 1. Even if the oscillation frequency is increased to increase the amount of heat generated,
The present invention provides a fuel atomization device that can effectively dissipate this heat, prevent changes in the characteristics of the oscillation element, and significantly improve combustion efficiency.

(Means for solving the IF!I problem) The feature of the configuration adopted by the present invention to solve the above-mentioned problems is that a heat dissipation fin is provided on the outer circumferential side of the balancer to dissipate heat generated by ultrasonic vibration. This is because it was established.

(Function) Since the heat generated by ultrasonic vibration can be dissipated to the outside by the radiation fins, the balancer can be effectively cooled together with the horn etc., and the oscillation element can be prevented from being exposed to high temperatures.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3.

1 and 2 show a first embodiment of the invention.

In the figure, 1 indicates an intake pipe provided on the intake side of the engine, and the intake pipe 1 is composed of a throttle body, an intake manifold, etc., and an intake passage 2 is formed inside thereof. The intake passage 2 communicates with the inside of an engine cylinder (none of which is shown) through an intake valve, etc., and air (outside air) that has been purified by an air cleaner (not shown) is directed into the cylinder in the direction of arrow A. It is designed to be drawn inward. Further, the intake pipe l is provided with a venturi portion IA located in the middle of the intake passage 2, and the venturi portion IA is provided in the intake pipe l.
A is designed to reduce the passage area of the intake passage 2 and increase the flow velocity of intake air.

3 is located upstream of the venturi part IA and is connected to the intake pipe l.
The throttle valve 3 is rotated by pressing an accelerator pedal (not shown), etc., and opens the intake passage 2 into the cylinder.
The flow rate of intake air sucked in through the valve is adjusted.

Reference numeral 4 indicates an injection valve located at the venturi portion IA and attached to the intake pipe l. The fuel is sprayed through the spray nozzle 4A in a direction substantially perpendicular to the axis 0-0.

Reference numeral 6 indicates a fuel atomization device disposed in the venturi portion IA of the intake pipe l in a direction perpendicular to the axis 0-0 so as to face the injection valve 4, and the fuel atomization device 6 is shown in FIG. As shown in FIG.
A horn 11 and a hollow balancer 12 each sandwiching each piezoelectric element 7 with a bolt 9 and a nut lO through a washer 8 etc. are integrally provided at the tip of the horn 11, and a metal plate such as a stainless steel plate is formed into a semicircle. A diaphragm 13 as a vibrator formed by curving it into a shape, a mounting bracket 14 located on the base end side of the horn 11 and provided at a 1/4 wavelength portion that does not participate in vibration, and the outer periphery of the balancer 12. Disc-shaped radiation fins 15, 15. provided on the sides. It is roughly composed of...

The fuel atomizer 6 is screwed onto the intake pipe l via a mounting bracket 14, and the diaphragm 13 is attached to the intake passage 2.
The balancer 12 faces the injection nozzle 4A of the injection valve 4 within the
together with each radiation fin 15 protrude outside the intake pipe l and come into contact with the outside air. Further, the bolt 9 is inserted inside the balancer 12 and each piezoelectric element 7, etc., and its both ends are screwed into the screw hole 11A of the horn 11 and the nut 10, so that the horn 11, the balancer 12, etc. A predetermined axial load is applied between the two.

Here, the fuel atomization device 6 generates vertical (axial) ultrasonic vibration by applying a high frequency voltage of about 40 to 60 KH2 from the outside to each piezoelectric element 7, and this vibration It is amplified by the horn 11, and the diaphragm 1
At the same time, the balancer 12 transmits the signal to the horn 1.
Vibrations are balanced against the 1st class. Then, the diaphragm 13 uses ultrasonic vibration to atomize the fuel injected from the injection valve 4 onto its inner surface to, for example, about 1 ouL, and transfers the atomized fuel F to the air drawn in the direction of arrow A. to form a homogeneous mixture. Further, each heat dissipation fin 15 provided on the balancer 12 radiates heat generated in the horn 11, the balancer 12, etc. by the ultrasonic vibration (for example, about 90°C) to the outside, and heats the horn 11, the balancer 12, etc. to 60°C, for example. It is designed to cool down to:

The present embodiment has the above-described configuration, and there is no particular difference from the prior art in that the fuel atomizer M6 promotes atomization of the fuel F injected from the injection valve 4.

However, in this embodiment, the balancer 12 of the fuel atomization device 6
A plurality of radiation fins 15.15. -... is established,
Each heat radiation fin 15 is connected to the balancer 12 and each piezoelectric element 7.
Since these are made to protrude outside the intake pipe l and come into contact with the outside air, the heat generated in the horn 11, balancer 12, etc. due to ultrasonic vibrations from each piezoelectric element 7 is effectively absorbed by each radiation fin 15. Even if a high frequency voltage of, for example, 40 to 60 KH is applied to each piezoelectric element 7, the horn 11, balancer 12, etc.
It is possible to reliably cool the piezoelectric element 7 to 0''C or lower, and it is possible to solve problems such as the characteristics of each piezoelectric element 7 being exposed to high temperatures, which may change, and the life of the piezoelectric element 7 may be shortened.

Therefore, in this embodiment, it is possible to further increase the oscillation frequency of the ultrasonic vibrations generated from each piezoelectric element 7 by applying a higher high-frequency voltage to each piezoelectric element 7 than in the prior art, thereby increasing the It has various effects, such as further promoting the atomization of F, reliably atomizing it to about 10JL+e, forming a uniform air-fuel mixture, and improving combustion efficiency.

Next, FIG. 3 shows a second embodiment of the present invention, and the feature of this embodiment is that the fuel atomization device is arranged in the intake passage so as to be parallel to the axis of the intake passage. .

In the figure, 21 indicates a cylinder of the engine, and the cylinder 2
A cylinder head 22 is mounted on the cylinder head 22, and the cylinder head 22 has an intake valve 24 that sucks the air-fuel mixture into the cylinder 21 from the intake port 22A in accordance with the reciprocating movement of the piston 23 sliding inside the cylinder 21. Also, an exhaust valve 25 is provided for discharging exhaust gas generated by combustion (explosion) of the air-fuel mixture within the cylinder 21 to the exhaust port 22B side. 26 indicates an exhaust pipe such as an exhaust manifold connected to the exhaust port 22B of the cylinder head z2, and the exhaust pipe 2
6 is an oxygen sensor 27 that detects the oxygen concentration in exhaust gas.
Or installed.

Reference numeral 28 indicates an intake pipe connected to the intake port 22A of the cylinder head 22, and the intake pipe 28 consists of a throttle body, an intake manifold, etc., and an intake passage 2 is provided inside the intake pipe 28.
9 is formed. The intake pipe 28 is provided with an injection valve mounting part 28A and a venturi part 28B located in the middle of the intake passage 29, and an abbreviated bent part 28C is formed downstream of the venturi part 28B. ing.

Reference numeral 30 indicates a throttle valve that is rotatably provided in the intake pipe 28 and located upstream of the injection valve mounting portion 28A, and the throttle valve 30 is similar to the throttle valve 3 described in the first embodiment. Similarly, the flow rate of suction air sucked in the direction of arrow A is adjusted.

Reference numeral 31 indicates an injection valve provided in the injection valve mounting portion 28A of the intake pipe 28. The injection valve 31 is disposed so as to be substantially parallel to the axis of the intake passage 29, and is connected to a fuel atomization device 33, which will be described later. It faces the diaphragm 37. The injection valve 31 is configured to inject the fuel F from the fuel pipe 32 to the diaphragm 37 on the downstream side via the injection nozzle 31A.

Reference numeral 33 indicates a fuel atomization device disposed in the intake passage 29 facing the injection valve 31 to atomize the fuel F injected from the injection valve 31, and the fuel atomization device 33 is connected to the first fuel atomization device 33. Almost the same as the fuel atomizer 6 described in the embodiment, a piezoelectric element 34 as one oscillation element is used. Horn 35, balancer 3
6. Vibration plate 37 as a vibrator and mounting bracket 3
The balancer 36 has a heat dissipation fin 3 on the outer circumferential side.
9,39. -... is provided. However, in the fuel atomization device W133, the mounting bracket 38 is formed in the shape of an elongated plate, and the left and right end sides of the mounting bracket 38 are connected, for example, to a gasket (not shown) between the throttle body and the intake manifold. The intake passage 29 is held in place and fixed in the middle of the intake passage 29 so as to allow the air-fuel mixture to flow therethrough.

The fuel atomizer 33 is disposed downstream of the injection valve 31 in a direction parallel to the axis of the intake passage 29, and the horn 3
5 is located on the upstream side in the intake passage 29 so that the diaphragm 37 faces the injection nozzle 31A of the injection valve 31A with slight eccentricity, and the balancer 36 is bent on the downstream side in the intake passage 29 together with each radiation fin 39. It is located near the portion 28C.

Thus, in this embodiment configured as described above, it is possible to obtain substantially the same effects as in the first embodiment. In particular, in this embodiment, the fuel atomization device 33 is disposed in the intake passage 2.
Since each heat dissipation fin 39 provided on the balancer 36 is positioned in the vicinity of the bent portion 28C of the intake pipe 28, the following effects can be obtained.

That is, the fuel F whose atomization is promoted by the diaphragm 37 of the fuel atomization device 33 flows downstream while mixing with the intake air in the direction of arrow A, and collides with each radiation fin 39. Since each of the heat radiation fins 39 radiates heat generated by ultrasonic vibration to the surroundings, the atomized fuel F is evaporated into a vapor shape by this heat.
It is possible to further promote atomization of the fuel F, and to form an air-fuel mixture that is more uniformly mixed with the intake air.

Therefore, the atomized fuel F is transferred to the bending portion 2 as in the prior art.
It is possible to prevent the heat from adhering to the inner wall of 8C as a wall film flow, and the heat from each radiation fin 39 can be effectively used to significantly improve combustion efficiency.

Note that in each of the above embodiments, the diaphragm 13 as a vibrator
(37) has been described as being curved into a semicircular shape, but the diaphragm 13 (37) may be formed in other shapes, for example, it may be formed in a cylindrical shape, with an injection nozzle 4 on the tip side.
A (31A) insertion hole may be drilled,
Further, the diaphragm 13 (37) may be slightly eccentrically opposed to the injection valve 4 (31) as shown in FIG. 3, or may be directly opposed to the injector 4 (31).

Furthermore, in each of the embodiments described above, the piezoelectric element 7 is used as the oscillation element.
Although two piezoelectric elements 7 (34) are provided, piezoelectric elements 7 (
The number of elements 34) may be one or three or more, and an oscillation element such as a magnetostrictive vibrator may be used instead of the piezoelectric element 7 (34).

〔Effect of the invention〕

As detailed above, according to the present invention, since the heat dissipation fins are provided on the outer circumferential side of the balancer to dissipate the heat generated by ultrasonic vibration, even when the oscillation frequency of the oscillation element is increased, the horn, balancer, etc. Can be effectively cooled,
In addition to preventing changes in the characteristics of the oscillation element, it is possible to further promote atomization of the fuel.In addition, by placing heat dissipation fins in the intake passage together with a balancer, etc.
The heat from the radiation fins evaporates the atomized fuel,
It can be mixed more uniformly with intake air, greatly improving combustion efficiency.

[Brief explanation of the drawing]

1 and 2 show a first embodiment of the present invention, FIG. 1 is a longitudinal sectional view showing the main part of an intake pipe with a fuel atomizer installed, and FIG. FIG. 3 is a longitudinal sectional view showing an enlarged longitudinal sectional view of an intake pipe, etc., to which a fuel atomization device is attached, showing a second embodiment. 1.28--Intake pipe, 2.29--Intake passage, 4.
31...Injection valve, 6.33-...Fuel atomization device, 7
．． 34--Piezoelectric element (oscillation element), 11.35--
Horn, 12.36-... Balancer, 13.37-...
Vibrator (diaphragm), 14.38...Mounting bracket,
15.39...Radiation fin, 21-...Cylinder, 2
2-...Cylinder head, 23-...Piston, 26-
...Exhaust pipe, 28 C-...Bend part. Patent applicant: Japan Electronics Co., Ltd. Agent: Kazuhiko Hirose, patent attorney
Naoki NakamuraFigure 1Figure 2Figure 3

Claims (3)

[Claims] (1) An oscillation element that generates ultrasonic vibrations, a horn provided on one side of the oscillation element to amplify the ultrasonic vibrations of the oscillation element, and a horn provided on the other side of the oscillation element with respect to the horn. a balancer for balancing vibrations; a vibrator provided at the tip of the horn to promote atomization of fuel injected from the injection valve into the intake passage; and a vibrator for positioning the vibrator in the intake passage. In a fuel atomization device consisting of a mounting bracket provided on the base end side of a horn,
A fuel atomization device characterized in that a heat dissipation fin is provided on the outer peripheral side of the balancer to dissipate heat generated by ultrasonic vibration. (2) The vibrator is located within the intake passage, and the balancer is mounted via the mounting bracket in a direction perpendicular to the axis of the intake passage, and the heat dissipation fin is connected to the outside air. The fuel atomization device according to claim (1), which is configured to face the fuel atomizer. (3) Mount the mounting bracket in a direction parallel to the axis of the intake passage so that the vibrator is located on the upstream side of the intake passage, and the balancer is located together with the radiation fins on the downstream side of the intake passage. 2. The fuel atomization device according to claim 1, wherein the fuel atomization device is configured such that the fuel atomized by the vibrator collides with the radiation fins to promote evaporation and mixing.