JPS6296771A - Intake pipe for internal-combustion engine - Google Patents

Abstract

PURPOSE:To enable more uniform distribution to each cylinder by constructing the captioned intake pipe such that the air weighed through a throttle valve is splitted into two layers, that is, an air layer and a mixture layer of air and fuel and the air layer impinges against the mixture gas layer near a bending section of an intake pipe. CONSTITUTION:A hollow tubular vibrator 1 and a fuel injection valve 2 constituting a supersonic fuel atomizer is arranged in an intake pipe collecting section 4 in the downstream of a throttle valve 3. The interior of the intake pipe collecting section 4 is splitted into two along the air flow direction by means of a partition board 5 and a cylinder 8 is connected to the lower section of said collecting section 4 splitted into two where said vibrator 1 is arranged while extending in the direction crossing perpendicularly with the partition board 5. A branch section 6 to be connected with each cylinder is jointed to the lower section of said cylinder 8. The tip of the intake pipe collecting section 4 is formed into a hemisphere 15 to change the direction of the air flowing-in from the upper layer section and face against a mixture gas flowing-in from the lower layer section so that it is possible to prevent impingement of fuel against the wall face.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an intake pipe for an internal combustion engine, and more particularly to an intake pipe provided with a single-point fuel injection valve for a multi-cylinder fuel-injected gasoline engine.

[Background of the invention]

2. Description of the Related Art In gasoline engines installed in automobiles and the like, fuel collides with the wall surface of an intake pipe that sends a mixture of air and fuel to a plurality of cylinders. Particularly in multi-syllable engines, fuel tends to collide at the bends in the intake pipe.

As a result, there was a problem that the air and fuel were not mixed sufficiently υ, resulting in poor combustion efficiency. As means for solving this problem, a method has been disclosed in which a fuel injection valve is provided in each cylinder to supply fuel from near the intake pipe, and a method in which fuel vaporization is promoted by heating the intake pipe. Furthermore, as disclosed in Japanese Patent Publication No. 52-37952 and Japanese Patent Publication No. 60-11224, a method of reducing the particle size of fuel using ultrasonic vibration is also known. However, in this case, although the particle size of the fuel is about 40 μm, there is a drawback that collision of the fuel at the bend in the intake pipe cannot be avoided. As a proposal to improve this point, JP-A-60-8
As disclosed in Japanese Patent No. 457, there is a structure in which the curvature of the bent portion of the intake pipe is reduced, but it has the drawback that two or more fuel injection valves are required, which increases the cost. Furthermore, as disclosed in Japanese Utility Model Application Publication No. 56-55763, a method has been proposed in which the intake pipe collection section is divided into two layers to speed up the transportation of fuel. There was a problem in that most of the supplied fuel collided with the wall of the intake pipe.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned points, and the seventh object is to use one fuel injection valve.
Another object of the present invention is to provide an intake pipe for an internal combustion engine that can evenly distribute fuel to a plurality of cylinders by preventing fuel from colliding with the bent portion of the intake pipe.

[Summary of the invention]

The present invention provides an intake pipe assembly for an internal combustion engine in which one fuel injection valve is provided downstream of one throttle valve in the intake pipe assembly part that sends a mixture of air and fuel to a plurality of cylinders. One end on the cylinder side of the section is of a sealed structure, and the intake pipe collecting section is separated into two layers by a partition plate with one end on the cylinder side open, and one layer is connected to the fuel injection valve and the air volume. A branch section is provided to supply a mixture of air and fuel, the other layer is supplied with only air, and the air and fuel mixture supplied from the two layers are provided near the closed end of the intake pipe gathering section. K to achieve the desired goal by colliding Aiki.
This is what was done.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an intake pipe for an internal combustion engine according to the present invention will be described below with reference to the drawings.

An embodiment of the present invention is shown in FIGS. 1 to 6.

FIG. 1 shows an example in which an embodiment of the present invention is applied to a multiple fuel injection type gasoline engine.

A hollow cylindrical vibrator 1 and a fuel injection valve 2 constituting an ultrasonic fuel atomization device are respectively disposed within an intake pipe collection section 4 on the downstream side of a throttle valve 3. This intake pipe gathering portion 4 is divided into two by a partition plate 5 parallel to the air flow direction. The hollow cylindrical vibrator 1 is disposed in the lower part of this two-divided intake pipe gathering section 4. Further, a cylinder 8 is connected to this lower part so as to be perpendicular to the partition plate 5, and a branch part 6 connected to each cylinder is connected to the lower part of this cylinder 8. This branch part 6 is joined to the intake boat part of each cylinder of the engine 7.

An air cleaner 10 is provided above the throttle valve 3 of the intake pipe collection section 4, and an air flow sensor 9 is provided downstream of this air cleaner 10. The engine 7 is provided with a crank sensor 11, a water temperature sensor 12, and an air-fuel ratio sensor 13, respectively. Signals from these sensors 9, 11, 12 degrees, and 13 are input to a controller 14, respectively, and is configured to optimally perform combustion control at a lean air-fuel ratio.

FIG. 2 is a sectional view from the top of the intake pipe. A cylinder 8 is joined to the cylindrical intake pipe gathering part 4 so as to be orthogonal thereto, and a plurality of branch parts 6 are joined to this cylinder 8. The tip of the intake air gathering portion 4 is hemispherical. The intake pipe gathering part 4, the cylinder 8, and the branch part 6 are in communication, so that air and fuel can flow therethrough. The length of the intake pipe gathering portion 4 is the hemispherical portion 15-! when fuel with a particle size of approximately 35 μm is supplied at the inlet of the cylindrical portion 40. In order to evaporate to 10 μm or less, the length is set to 160 m or more. If the particle size of the supplied fuel is large, it is necessary to further increase this length. For example, if 100 μm of fuel is supplied, the length needs to be 1000+++s+ or more.

FIG. 3 is a side sectional view of the intake pipe. Intake pipe gathering part 4
is divided into two by a partition plate 5. A cylinder 8 is joined to the lower part of the two parts so as to be orthogonal to each other, and a branch part 6 is joined to the cylinder. Although the branching portion 6 is bent approximately 90 degrees, the fuel in the branching portion 6 has a thickness of 10 μm or less, and no fuel collision occurs in this portion.

FIG. 4 is a detailed view of the air confluence section of the intake pipe collection section 4. As shown in FIG.

A cylinder 8 is orthogonal to the intake pipe gathering part 4, and a branch part 6 is joined to the cylinder 8. Further, the tip of the intake pipe gathering portion 4 has a hemispherical shape 15. In this case, in the hemispherical portion 15,
It is safe to minimize air turbulence.

If air turbulence is large in the hemispherical portion 15, the fuel tends to collide with the wall surface of the intake pipe. Therefore, it is necessary to process the joints of each cylinder and the joints of hemispherical parts so that they are smooth and have no edges.

FIG. 5 is a side view of the intake pipe gathering section 4. FIG. The partition plate 5 is fixed to the intake pipe gathering part 4. In this case, the partition plate 5 needs to be longer by L with respect to the position of the perpendicular cylinder 8. As a result, the air flowing in from the upper part changes direction at the hemispherical part 15 and faces the mixture of air and fuel flowing in from the lower part, thereby preventing the fuel from colliding with the wall surface. The length of L is suitably the same as the height Da of the lower layer.

FIG. 6 is a configuration diagram in which the fuel atomizer 1, the fuel injection valve 2, and the upstream intake pipe assembly 16 are attached to the intake pipe assembly 4. As shown in FIG. The fuel atomizer t1 and the fuel injection valve 2 are fixed to the fuel injection valve container 17. The intake pipe gathering portion 16 is joined to the injection valve container 17, and the direction of the intake pipe can be changed.

The operation of this embodiment configured as described above will be explained below. The diameters of the intake pipe gathering portion 4 and the intake pipe gathering portion 16 are:
Since it is larger than the branch part 6, the air flow velocity is smaller than that of the branch part. Therefore, the inertial force of the fuel in the intake pipe gathering section 4 is reduced, and the collision of the fuel against the wall surface at the bend is reduced.

In addition, by reducing the diameter of the branch 6, the air flow velocity at the branch increases, the transport speed of the liquid film increases, the evaporation of fuel droplets is promoted, and the air is filled downstream of the throttle valve. Since the time is reduced, combustion within the cylinder is improved and the transient response of the engine is also improved.

Although the intake pipe collecting section 4 is divided into two parts by the partition &5, the air flow velocity within the pipe is almost the same as when there is no partition plate 5, and depends on the pipe diameter of the intake pipe collecting section 4.

FIG. 7 is a sectional view from above showing a method of supplying fuel to the hollow cylindrical vibrator. Fuel injection valve 2 is a hollow circle I\V
Spray fuel inside 1. The fuel is atomized on the inner surface of the hollow cylinder 1. The atomization device and the fuel injection valve 1 are fixed to the fuel injection valve container 17 with screws or the like. The fuel injection valve container 17 has flanges at both ends. Atomization device in the horizontal plane,
Since the fuel injection valve is provided, the structure can be made compact.

FIG. 8 shows another example of the method of supplying fuel to the hollow cylindrical vibrator 1. In FIG. FIG. 8(a) is a side view, and FIG. 8(b) is a top view.

The hollow cylindrical vibrator 1 is disposed on the lower side of the intake pipe gathering section 4. The atomization device is installed at the bottom of the collecting section. on the other hand,
The fuel injection valve 1 is attached to the side wall of the intake pipe gathering section 4.

The horn 18 of the atomizer and the fuel injection valve 2 are installed so as to be perpendicular to each other.

In this case, the atomization device can be installed at a symmetrical position with respect to the horizontal direction in the intake pipe collecting section 4, and has a symmetrical influence on the air flow in the intake pipe, so that
This has the effect of evenly distributing fuel.

FIG. 9 shows another example of a method of supplying fuel to a hollow cylindrical vibrator. A hollow cylindrical vibrator 1 is disposed in a lower part of an intake pipe assembly section 4 divided into two parts, and a fuel injection valve 2 is disposed on the upstream side thereof. The fuel injection valve 2 is arranged so that the fuel injected from the fuel injection valve 2 comes into contact with the entire inner circumference of the hollow cylindrical vibrator 1. Since the fuel is atomized around the entire circumference of the hollow cylindrical vibrator 1, the fuel flow rate at which the fuel can be atomized increases. Since the fuel injection valve 2 is provided upstream of the lower layer, air flows in from around the injection valve 2. Therefore, the fuel atomized by the hollow cylindrical vibrator 1 is surrounded by an air layer, thereby suppressing the collision of the fuel with the wall surface of the intake pipe. Furthermore, by arranging the injection valve 1 on the upstream side of the lower layer, air flows more easily toward the upper layer than in the lower layer, and the air flow velocity on the upper layer side increases. Therefore, the flow velocity of the air that collides with the fuel at the bend in the intake pipe increases, so that the inertial force of the fuel colliding with the bend can be reduced and collision with the wall surface can be prevented.

In this case, the shape of the fuel injection valve 1 is desirably streamlined in order to reduce air resistance.

FIG. 10 shows another embodiment of the method for supplying fuel to the hollow cylindrical camera element 1. In FIG. A hollow cylindrical oscillator 1 is disposed on the lower side of the intake pipe gathering portion 4, and a fuel injection valve 2 is disposed so that fuel comes into contact with the entire circumference of the inner surface of the hollow cylindrical oscillator 1. In this case, the fuel injection valve 2 is disposed at a curved portion of the intake pipe gathering portion 16.

As a result, even if the fuel injection valve 2 is disposed outside the intake pipe, fuel can be supplied to the entire inner circumference of the hollow cylindrical vibrator, so that air resistance due to the injection valve can be reduced.

Figures 11.12 are other embodiments of the arrangement of the throttle valves.

By arranging the throttle valve 1 near the fuel injection valve 2 and the atomization device, the volume of the intake pipe downstream of the throttle valve υ can be reduced, which reduces the time required to fill the air in the engine. Transient response is improved.

FIG. 13 shows the structure of an obstacle provided upstream of the hollow cylindrical vibrator 1. FIG. 13 (As in the case of a hunchback, by providing an obstacle 18 at the upstream part of the hollow cylindrical vibrator 1 disposed in the lower part of the intake pipe collecting part 4, the air flow velocity in the lower part of the intake pipe collecting part is reduced. It is possible to reduce the inertial force of the fuel.Also, when the air flow rate increases due to the fuel supplied from the fuel injection valve, the amount flowing into the air without contacting the hollow cylindrical vibrator 1 is reduced. In addition, since air flows into the lower layer from around the obstacle, it envelops the fuel and prevents fuel from adhering to the wall. This increases the inertial force of the air that collides with the fuel near the bend, and prevents the fuel from colliding with the intake pipe wall at the bend.The shape of the obstacle is designed to minimize air resistance. , and in order not to disturb the flow, as shown in Figure 13 (
The conical shape shown in a) or the streamlined shape shown in (b) is most likely to be dyed.

A conical shape has the advantage of being easier to process than a streamlined shape. The material should be aluminum, duralumin, or synthetic resin in consideration of durability.

FIG. 14 shows the shape of the partition plate 5 that divides the intake pipe gathering portion 4 into two. The shape of the tip of the partition plate 5 is such that air turbulence is reduced at the tip. Figure 14 (a
), since the surface of the tip is perpendicular to the flow, a boundary layer of air is likely to be generated from the tip, resulting in large air turbulence. For this reason, large air resistance occurs on the partition plate, causing a decrease in output in operating regions where the amount of air is large.

As shown in Figure 14), (C), (d), and (e), the development of the boundary layer can be suppressed by making the tip thinner or rounded. The material is preferably aluminum, duralumin, or synthetic resin in consideration of durability and workability.

FIG. 15 shows the arrangement of the partition plate 5 that divides the intake pipe collection section 4 into two. When divided into two as shown in FIG. 15(a), the amount of air flowing into the upper layer and the lower layer becomes equal. Also,
Attaching the partition plate 5 is also easy. As shown in FIG. 15(b), when the upper layer is made larger, the amount of air flowing through the upper layer increases, and the amount of air that opposes and collides with the fuel increases, making it easier to prevent the fuel from colliding with the wall surface. However, it is difficult to arrange the hollow cylindrical vibrator. If the upper layer is made smaller as shown in FIG. 15(C), it becomes easier to mount a hollow cylindrical vibrator or the like. The airflow resistance increases due to the installation of the hollow cylindrical vibrator, so the amount of air decreases. In this case, it is necessary to set the lower layer to the upper layer by 5=5 or about 426.

FIG. 16 shows the shape of divided passages within the collecting section. As shown in (a), when the intake pipe assembly section 4 is divided by a flat partition plate 5, processing is easy and the area of the passage of the intake pipe assembly section 4 is hardly reduced. Figure 15, c.

When a passage is formed into a cylindrical or elliptical shape as shown in d and e, it is necessary to form a smooth concave or convex shape at the entrance to reduce air resistance. In particular, the elliptical shape (d) has the advantage of hardly losing passage area. Processing is easy due to integral molding such as casting.

FIG. 17 shows another embodiment of the present invention. Two branch parts 6 are joined to the intake pipe gathering part 4 in the horizontal direction. Its tip further branches into two. The fuel whose direction has been bent at the intake pipe gathering section 4 is sucked into the branch section 6.

This configuration allows fuel to be distributed to each cylinder. By setting the angle θ of the branch portion of the intake pipe to 100 degrees or less, collision of fuel can be prevented even when the particle size is 40 μm. Moreover, since it can be arranged in a horizontal plane, it has a compact configuration. Since fuel can be distributed to each air volume without increasing the angle of the curved portion 9 of the intake pipe, collisions of fuel against the wall surface of the intake pipe are reduced. In addition, the resistance of the intake pipe passage is small,
Furthermore, since the inertia effect of intake air can be utilized, there is an effect of increasing the output.

FIG. 18 is a side view of the intake pipe shown in FIG. 17. The intake pipe collection section 4 is divided into two parts by a partition plate 5. The tip of the intake pipe gathering part is shaped like a hemisphere. The air in the upper layer divided into two passes through the hemispherical portion, and the air in the lower layer flows directly from the orthogonal cylinder 8 into the branch portion 6.

According to the embodiment shown in FIGS. 17 and 18, the hollow cylindrical vibrator 1 is arranged in the lower layer divided into two parts by the partition plate 5 as shown in FIG. The fuel atomized by the hollow cylindrical sensor 1 is mixed with the air in the lower layer and transported, but it collides with the air in the upper layer near the curved part, passes through the orthogonal cylinder 8, and flows into the branch part 6. do. This configuration prevents fuel collision at the bend in the intake pipe, reduces air flow resistance, and makes it more compact, improving output and improving transient response of the engine. improves. Furthermore, since the number of fuel supply devices can be reduced to one, costs are reduced. Although the fuel supply device has been described above using an injection valve and an ultrasonic atomizer, it is also effective to use an injection valve alone or a combination of an atomization device that uses high-speed airflow and an injection valve. In this case, it is necessary to change the distance from the fuel supply position to the hemispherical part of the intake pipe gathering part 4 depending on the particle size of the supplied fuel. For particle size 1100p, this distance is more than 1000m, and for 40Atm, this distance is 16
It needs to be 0m or more.

FIG. 20 shows another embodiment of the invention. The 22 branch parts 6 are attached horizontally to the intake pipe collecting part 4 so as to be inclined at an angle θ with respect to the axial direction of the intake pipe collecting part 4. Its tip further branches into two. The fuel whose direction has been bent at the intake pipe gathering section 4 is sucked into the branch section 6. This configuration allows fuel to be distributed to four cylinders. Since the angle θ of the branch portion of the intake pipe can be made small, the passage resistance of the intake pipe is small, and it is possible to prevent the fuel from colliding with the wall surface of the intake pipe. Furthermore, the inertial effect of the intake air can be utilized during the 1st and 2nd breaths and the 3rd and 4th breath. On the other hand, since the branch part 6 is attached at an angle θ1 with respect to the intake pipe gathering part 4, the ventilation resistance is small and the inertial effect can be utilized, which has the effect of increasing the engine output.

21 is a diagram showing the operation of the embodiment shown in FIG. 20.

A hollow cylindrical vibrator 1 is disposed below the layer divided into two by a partition plate 5. The fuel atomized by the hollow cylindrical vibrator 1 is mixed with the air in the lower layer and transported, but it collides with the air in the upper layer near the bend 9, passes through the orthogonal circle/tube 8, and is transported to the branch 6.
flows into.

〔Effect of the invention〕

As described above, according to the present invention, the air metered by one throttle valve in the intake pipe of an internal combustion engine is divided into two layers, one layer containing only air and the other layer containing a mixture of air and fuel. By making the air layer collide with the mixture layer near the bend in the intake pipe, it is possible to prevent fuel from colliding with the wall of the intake pipe at the bend, and the fuel is evenly distributed to multiple cylinders. be able to.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the overall structure of an embodiment of the intake pipe of an internal combustion engine according to the present invention, FIGS. 2 and 3 are horizontal and vertical sectional views, respectively, of the intake pipe shown in FIG. 5 and 5 are cross-sectional views showing the bent portion of the intake pipe shown in FIG. 1, and FIG.
FIGS. 7 to 10 are cross-sectional views showing the method of supplying fuel to the hollow cylindrical sensor of the intake pipe according to the present invention, and FIGS. 11 and 12 are the main parts of the figure. 13 is a sectional view showing the arrangement of the throttle valve according to the invention; FIG. 13 is a sectional view of the obstacle according to the invention; FIG. 14 is a sectional view of the partition plate according to the invention;
5 to 18 are cross-sectional views of the intake pipe according to the present invention, the first
9 to 21 are cross-sectional views showing other embodiments of the present invention. 2... Fuel injection valve, 3... Throttle valve, 4... Intake pipe gathering portion, 5... Partition plate, 6... Branch portion, 8... Cylindrical.

Claims (1)

[Claims] 1. In the intake pipe of an internal combustion engine in which one fuel injection valve is provided downstream of one throttle valve in the intake pipe assembly part that sends a mixture of air and fuel to a plurality of cylinders, One end on the cylinder side has a sealed structure, and this intake pipe gathering part is separated into two layers by a partition plate with one end on the cylinder side open, and one layer is connected to the fuel injection valve and the cylinder. A branch part is provided to supply a mixture of air and fuel, and only air is supplied to the other layer, and the air and mixture supplied from the two layers are provided near the closed end of the intake pipe gathering part. An intake pipe of an internal combustion engine characterized by colliding.