JPS6138154A - Fuel supply device in internal-combustion engine - Google Patents

Abstract

PURPOSE:To promote the atomization of fuel to obtain a satisfactory mixture, by providing a vibration exciter having a plurality of vibrating surfaces disposed in an intake-air passage in opposite to each other and a fuel supply mechanism for feeding fuel toward the vibrating surfaces. CONSTITUTION:A vibrator element holding section 3 is projected into an intake- air passage 2 in a housing 1, and an solenoid valve attaching boss section 4 is formed on the outside of the intake-air passage 2. Further, ultrasonic vibrators 5 are attached to the inner opposing surfaces of the holding section 3, each of which is constituted such that an element 6 having both surfaces applied with electrodes 7, 8 is disposed in a casing 10 through the intermediary of a supporting member 9 made of resilient materials. A fuel supply nozzle 11 having a pair of jet ports at its front end is arranged on the vibrating surface 5a which is the outer surface of the electrode 7. Further, the front end part 12a of a solenoid valve 12 attached to the attaching boss section 4 is connected to the base end of the nozzle 11 through the intermediary of a seal member 13. With this arrangement, fuel is repreatedly vibrated between a plurality of vibrating surfaces 5a to attain a predetermined purpose.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an improvement in a fuel supply system for an internal combustion engine that uses an ultrasonic vibrator to atomize fuel. In devices that ignite and burn an air-fuel mixture, it is necessary to sufficiently atomize the fuel and mix it with air in the fuel supply device in order to homogenize the air-fuel mixture, prevent fuel from adhering to walls, or improve distribution characteristics.

FIG. 8 shows a fuel supply device previously proposed to achieve sufficient atomization of such fuel (Internal Combustion Engine, Vol. 19, No. 3, published by Sankaido, 1980). This is intake passage 4
A vibrating plate 42 having a vibrating surface 42a that is substantially parallel to the flow direction of the intake air is disposed within the arm portion 430 that supports the vibrating plate C, and an element 45. An ultrasonic vibrator 44f consisting of an electrode 46 and a fixing member 47 is attached, and a fuel injection valve is disposed opposite the vibration surface 42&, and the vibration surface 42a is arranged from the fuel injection valve section to the vibration surface 42a. The fuel injected toward the fuel is subjected to ultrasonic vibrations and becomes atomized.

Problems to be Solved by the Invention However, in the above configuration, the fuel injected from the fuel injection valve 48 collides with the vibrating surface 42a only once, and the fuel is atomized on that one occasion. When attempting to atomize a large amount of fuel, sufficient atomization performance may not be obtained, and droplets with relatively large particle sizes may be mixed in the air-fuel mixture.

Means for Solving the Problems In this invention, in order to solve the above problems,
A plurality of vibrating surfaces of the vibrating mechanism arranged in the intake passage are arranged to face each other, and fuel is injected and supplied toward the vibrating surfaces by a fuel supply mechanism consisting of a fuel injection valve or the like. be.

Effect: Due to the arrangement of multiple vibrating surfaces facing each other as described above,
The injected fuel is reflected from each vibrating surface and collides with it multiple times, and each time it collides, it is vibrated and becomes droplets with smaller particle sizes. In particular, if the droplets are not sufficiently atomized and are large, their penetrating power is large, so they will collide many times, and eventually they will become sufficiently atomized and become inhaled air. Mix it.

Embodiment FIG. 1 is a sectional view showing a first embodiment of the present invention. In the figure, reference numeral 1 denotes a housing having an intake passage 2, in which a vibrator holding part 3 having a U-shaped cross section is formed to protrude into the intake passage 2, and an electromagnetic valve mounting boss part 4 is provided on the outside thereof. is formed. Ultrasonic transducers 5 in the so-called thickness transducer shape, which are shown in detail in FIG. 2, are mounted on the inner facing surfaces of the transducer holding portions 3, respectively. This is a plate-shaped element 6 made of ferroelectric material, etc., with electrodes 7 and 8 pasted on both sides, respectively, and housed in a case 10 via a frame-shaped support member 9 made of an elastic material such as rubber. The outer surface of the electrode 7 serves as a vibrating surface 5a, and both vibrators 5 are attached to the vibrator holding portion 3 of the housing 1 with their vibrating surfaces 5a facing each other. A fuel supply nozzle 11 having a pair of nozzle holes 11a at its tip facing each vibration surface 5a is arranged between the two vibration surfaces 5a, and is attached to the magnetic valve mounting boss 4 in the evening. The distal end 12a of the electromagnetic valve 1.2 is connected to the base end of the fuel supply nozzle 1.1 via a seal member 13.

The electromagnetic valve 12 is opened and closed by a drive pulse signal from a control circuit (not shown), and is configured to meter fuel at a constant fuel pressure sent through the fuel supply pipe 14 according to its opening time and introduce it into the fuel supply nozzle 11. The injected fuel flows into the nozzle hole 11 at the tip of the fuel supply nozzle J,1.
A is injected onto each vibrating surface 5a, and as described above, the particles are atomized by being subjected to the vibrations of the ultrasonic vibrator 5 a plurality of times. The position where the fuel collides with the vibrating surface 5a from the nozzle hole 11& is preferably the center of the vibrating surface 5a or a position slightly upstream of the center in consideration of the intake flow velocity.

Furthermore, if the thickness transducer type ultrasonic transducer 5 used in this embodiment is driven in the absence of fuel, there is a risk of damage due to temperature rise, so it should be driven in synchronization with the fuel injection timing. It is necessary to set the drive start timing to be the same as or slightly delayed from the injection start of the solenoid valve 12.

Next, FIG. 3 shows a second embodiment of the present invention. This flame 7/i (in the example, a pair of arm parts 21., 21 are facing each other, in a vertical shape 7; A vibrating plate 22 having a vibrating surface 22 a is supported, and an element 24 . Electrode 25
A so-called Langevin-type ultrasonic transducer 23 consisting of an identification member 26 and an identification member 26 is attached. A fuel supply nozzle 11 similar to that of the first embodiment is arranged together with a solenoid valve 12 between the two folding surfaces 22a. The Langevin-type ultrasonic transducer 23 used in this embodiment is as follows:
It has the advantage that there is no risk of damage even if it is driven in the absence of fuel.

Note that even in this case, it is desirable to drive in synchronization with fuel injection from the point of view of power consumption.

Next, FIG. 4 shows a third embodiment in which the configuration of the second embodiment is partially changed.
An example is shown. This is because a fuel passage 27 is formed inside one of the diaphragms 22 and the arm portion 21, and fuel is injected from the fuel injection valve 28 from a nozzle hole 27a opened at the center of the oscillating surface 22a toward the other oscillating surface 22a. The configuration is such that injection is performed.

Next, FIG. 5 is a sectional view showing a fourth embodiment of the present invention, in which the tip of the arm section 21 equipped with the ultrasonic transducer 23 is
A cylindrical vibrating portion 31 having a rectangular cross section is provided, and vibrating surfaces 31a #31a facing each other are formed inside the vibrating portion 31. Similarly to the third embodiment, a fuel passage 27 is formed in the arm portion 21, and one vibration surface 31 a
The configuration is such that all fuel injection is performed in preparation for this.

Further, in the $5 embodiment shown in FIG. The same fuel supply nozzle 11 as in the second embodiment is inserted and arranged in a non-contact manner.

In the fourth and fifth embodiments described above, the pair of vibrating surfaces 3], a, and 31a are driven by a single ultrasonic transducer 23, which reduces the number of parts and power consumption. It will be advantageous.

Next, the sixth embodiment shown in FIG. 7 is an example in which the above-mentioned fourth and fifth embodiments are partially modified. A cylindrical inner cylinder 32 and an outer cylinder 33 are fixedly installed, and the outer circumferential surface 32 of the inner cylinder 32
a and the inner circumferential surface 33a of the outer cylinder 33 serve as vibration surfaces facing each other. A poppet valve for fuel diffusion is disposed so as to face the upstream end of the inner cylinder 32, and the fuel sent through the electromagnetic valve 35 enters the poppet valve 34. It is configured to be supplied radially between both vibrating surfaces 32a and 33a.

Effects of the Invention As is clear from the above explanation, in the fuel supply system for an internal combustion engine according to the present invention, the fuel is repeatedly vibrated between a plurality of vibrating surfaces, and in particular, the first collision with the vibrating surface produces large particles. Since the droplets that remained the same diameter are reliably atomized by another collision, it is possible to prevent droplets from adhering to the intake passage wall even when the fuel injection capacity is large, resulting in extremely good properties. It becomes possible to form a mixture of

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention, FIG. 2 is an enlarged sectional view of an ultrasonic transducer in this first embodiment, and FIGS. 3, 4, 5, and 6. and FIG. 7 are sectional views showing a second embodiment, a third embodiment, a fourth embodiment, a fifth embodiment, and a sixth embodiment of the present invention, respectively, and FIG. 8 is a sectional view of a conventional fuel supply device. It is a diagram. DESCRIPTION OF SYMBOLS 1... Housing, 2... Intake passage, 5... Ultrasonic vibrator, 5a... Vibration surface, 11... Fuel supply nozzle, 12... Solenoid valve, 21... Arm part , 22...
- Vibration plate, 22 a... Vibration surface, 23... Ultrasonic vibrator, 27... Fuel passage, 28... Fuel injection valve, 3
DESCRIPTION OF SYMBOLS 1... Vibration part, 31a... Vibration surface, 32... Inner cylinder, 33... Outer cylinder, 32a, 33a... Vibration surface, 34
...Poppet valve, story...Solenoid valve. 1----- -- City (ψ force dm + 1------------Ichidaitomura A to Saitsukakeshi f2--
---------One ton, one valve, Figure 2, Figure 4, Figure 6

Claims (1)

[Claims] (1) A fuel supply device for an internal combustion engine, comprising a vibrating mechanism having a plurality of vibrating surfaces arranged opposite to each other in an intake passage, and a fuel supply mechanism injecting and supplying fuel toward the vibrating surfaces. .