JP2002364472A - Intake device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a structure of an intake passage in a device for generating a turning flow in an combustion chamber of an engine. SOLUTION: The air passing through a throttle valve 1 diverges at a collector part 3 and is led to an independent intake pipe 4. Then, the air passes an intake valve 5 and is sucked into a cylinder 6. An auxiliary pipe 7 is provided in the independent intake pipe 4, and two intake passages 8 are provided for bypassing it. The intake passage 8 is formed to be in a straight passage between the collector part 3 and a nozzle part of a fuel injection valve 10. The auxiliary valve 7 is opened usually. When performing lean combustion or when it is required to improve combustion such as at idling or at a low temperature, the auxiliary valve 7 is closed and the intake air is supplied to the cylinder 6 from the intake passage 8. Thus, the structure of the bypass intake passage for generating the turning flow in the combustion chamber can be simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an intake device for supplying air and fuel to a combustion chamber of an engine.

[0002]

2. Description of the Related Art In a conventional intake pipe, an attempt has been made to positively generate a swirling flow in a combustion chamber in a specific operating state of an engine in order to increase the efficiency of combustion. Specifically, an auxiliary valve and a bypass passage that bypasses the auxiliary valve are provided in the intake main passage, and the auxiliary valve is closed in a specific operation state of the engine, so that air entering the combustion chamber from the bypass passage flows to the inlet of the combustion chamber. As a result, a swirling flow is formed in the combustion chamber by entering from a specific biased position.

[0003]

However, the conventional apparatus has a problem that it is difficult to form the bypass passage.

SUMMARY OF THE INVENTION It is an object of the present invention to improve the arrangement of a divided passage, an auxiliary valve, and a bypass passage for generating a swirling flow in a combustion chamber so that the structure can be easily formed.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an independent intake pipe located between a collector and an engine head, the auxiliary valve being closed at the time of lean combustion, idling or low temperature, the fuel injection valve, and the auxiliary valve being bypassed. This is achieved by forming a straight passage connecting the collector and both sides of the injection port of the fuel injection valve.

Preferably, the distance between the upstream opening and the downstream opening of the two intake passages installed in the independent intake pipe is equal to the distance between the upstream opening and the downstream opening of the independent intake pipe. About equal to the distance between

[0007] Preferably, the flow of air ejected from the two intake passages and the flow of fuel ejected from the fuel injection valve are substantially parallel to each other.

[0008] More preferably, the flow of air ejected from the two intake passages and the flow of fuel ejected from the fuel injection valve collide on the surface of the intake valve of the internal combustion engine.

[0009] Preferably, the upstream openings of the two intake passages are opened in the collector connected to the independent intake pipe in which the downstream openings of the two intake passages are opened. .

[0010] More preferably, the opening degree of the auxiliary valve is changed according to the operating state of the internal combustion engine.

Still more preferably, the two intake passages bypassing the auxiliary valve are constituted by straight passages penetrating the intake passage wall forming an independent intake pipe.

[0012]

1 and 2 show a first embodiment of the present invention. After passing through the throttle valve 1, the intake air passes through the upper collector 2, and is separated into left and right partitioned collectors 3a and 3b. Further, the air is branched from these collectors into an independent intake pipe 4, passes through an intake valve 5, and is sucked into a cylinder 6.
Here, an auxiliary valve 7 and an intake passage 8 bypassing the auxiliary valve 7 are provided in order to generate a swirling flow in the cylinder. Normally, the auxiliary valve 7 is open. However, when performing lean combustion, or when it is desired to improve combustion such as at idle or low temperature, the auxiliary valve 7 is opened.
Is closed, and the intake air is supplied into the cylinder 6 from the intake passage 8. In this manner, when a directional air flow is supplied to the position where the intake valve 5 is provided in the direction indicated by the one-dot chain line in FIG. Is formed. Fuel is supplied from a fuel injection valve 10. Although FIG. 1 shows an example of application to a V-type engine, the invention can also be applied to an in-line engine.

FIG. 2 shows the directions of the air flow and the fuel spray shown in FIG. The right side of the dotted line (a) shown in FIG.
At 0, the engine head 15 is on the left side. The intake air is supplied from an intake passage 8 bypassing the auxiliary valve 7 to form a swirling flow 9 in the cylinder 6. Here, although the fuel injection valve is not shown, the direction of the air flow 12 ejected from the intake passage 8 is made to coincide with the direction of the fuel spray 11 so that the air flow 12 and the fuel
1 is configured so as not to cross up to the intake valve 5. With this configuration, the fuel spray 11 is not deflected by the high-speed airflow 12 and the intake valve 5
Directly hit. If the fuel spray 11 is configured to collide with the high-speed airflow, the fuel spray 11 collides with the wall surface 15 of the intake pipe, a liquid film is formed, and combustion deteriorates. By thus making the direction of the air flow 12 and the direction of the fuel spray 11 substantially parallel, a swirling flow can be formed in the cylinder 6 without deteriorating the properties of the fuel spray 11. The outlet 13 of the intake passage 8 opens at the boundary (a) and does not protrude toward the head. Further, a cutout 14 is formed on the head side so as not to obstruct the airflow 12 ejected from the intake passage 8. As shown in FIG. 2, the positions of the fuel injection valve and the outlet of the intake passage 8 are substantially at the same height. In this embodiment, the air flow 12 is aimed at the gap when the intake valve 5 is open, and the fuel spray 11 is injected over the intake valve 5. With such a configuration, the amount of unburned hydrocarbons emitted from the engine can be reduced, and the combustion in the lean state can be stabilized.

FIGS. 3 and 4 show a second embodiment, and show the structure of the intake passage 8. FIG. In FIG. 3, an outlet 13 of the intake passage 8 is opened at the tip of the fuel injection valve 10. (B)
FIG. 4 is a diagram viewed from the direction of the arrow of FIG. Here, the intake passage 8 is provided on both sides of the fuel injection valve 10. That is, two intake passages 8 are provided for each cylinder. Therefore, there are two outlet portions 13 of the intake passage 8. Reference numeral 21 denotes an opening provided for ejecting the fuel spray 11 from the fuel injection valve 10. The outlets 13 are provided on both sides of the opening 21. FIG. 3 shows an example of a V-type engine, but the present invention can be similarly applied to a serial engine as shown in FIG. As described above, the present invention can be applied to all engines such as an in-line engine, a horizontally opposed engine, and a V-type engine.

FIG. 5 shows a third embodiment, in which a V-type engine is used. An opening 22 on the upstream side of the intake passage 8 that bypasses the auxiliary valve 7 is open to the collector 3b.
In the case of the V-type engine, the collector is divided into two of the collectors 3a and 3b by a partition wall 23. In this case, pressure fluctuations in the independent intake pipe 4 cause intake inertia supercharging, and the cylinder 6 is filled with air. However, as shown in FIG. 1, the intake passage 8 does not correspond to the independent intake pipe 4, and the collector 3a of another bank is not provided.
, The pressure wave in the independent intake pipe 4 escapes to the collector 3a of another bank, and the inertia supercharging effect is reduced. Therefore, as shown in FIG.
The opening 22 of the intake passage 8 provided at the opening 3 is opened to the collector 3 b corresponding to the independent intake pipe 4. In this case, since the pressure wave propagates in the intake passage 8 and the independent intake pipe 4 in the same manner, the inertia supercharging effect does not decrease. In addition, the distance (A to B) between the openings at both ends of the passage and the corresponding distance (A to B) in the independent intake pipe 4 are the same so that the propagation of the pressure wave becomes the same in time. Need to be If they are the same, the peak time of both pressure waves coincide with each other, so that the effect is increased.

FIGS. 6 and 7 show a fourth embodiment. FIG. 6 shows the structure of the intake pipe viewed from above, and FIG. 7 shows a longitudinal section of FIG. The intake passages 8a provided on both sides of the fuel injection valve 10,
The air flow 12 from 8b is configured to sandwich the fuel spray 11 from the fuel injection valve 10. Further, the fuel spray 11
Is made to hit inside the position where the air flow 12 on the intake valve 5 hits. In this way, the fuel spray 11 is collected at the center without dispersing outside the intake valve 5. That is, the airflow 12 exhibits an effect like an air curtain,
Dispersion of the fuel spray 11 is prevented. The fuel spray 25 flowing into the cylinder 5 concentrates in the vicinity of the spark plug 24 and becomes rich around the spark plug 24 even when the supply air-fuel ratio is set to lean, so that stable combustion can be performed without misfiring.

When the position of the fuel injection valve 10 and the position of the intake passage 8 are set to the same height as shown in FIG. 2, it is necessary to provide a cutout 14 in the engine head, but as shown in FIG. By providing the intake passage 8 downstream of the fuel injection valve 10 on the side, the intake passage 8 can be formed without processing the engine head 26.

FIGS. 8 and 9 show a fifth embodiment, which is another embodiment of another means for forming a swirling flow in the cylinder 6. FIG. This is a method in which an auxiliary valve 29 is provided in the independent intake pipe 4 to give a drift to the air flow. In this case, as shown in FIG. 9, a part of the auxiliary valve 29 is cut out to give a deviated air flow. The shapes of the notches 28a and 28b are located on both sides of the injection port of the fuel injection valve 10. By doing so, as shown in FIG.
Since the fuel spray from the fuel injection valve 10 is sandwiched by the airflow, the fuel spray is concentrated at the center of the cylinder.

Generally, in an automobile, the amount of intake air, the amount of fuel,
The air-fuel ratio and the like are controlled using a microcomputer. In the present invention as well, the air-fuel ratio and the degree of opening of the auxiliary valves 7 and 29 are written into the memory element in a map form, and the control values are read. FIG. 10 shows an example of an air-fuel ratio map, and FIG. 11 shows an example of an auxiliary valve opening degree map. In these maps, the vertical axis represents the engine speed Ne, and the horizontal axis represents the fuel injection amount TP. The example of FIG. 10 is a map of the set target air-fuel ratio for controlling the lean combustion engine, and the target air-fuel ratio differs depending on the operation state. FIG. 11 is a map of the set values of the opening degrees of the auxiliary valves 7 and 29. The larger the numerical value, the smaller the opening degree. That is, the larger the numerical value, the larger the amount of air flowing through the intake passage 8. By changing the opening degree of the auxiliary valves 7 and 29 depending on the operation state, an optimum swirl flow can be obtained, and an optimum air-fuel ratio can be obtained in each operation state.

FIG. 12 shows a sixth embodiment. FIG. 12 shows a case where the two intake passages 8 aim inside the intake valve 5, and forms a vertical swirling flow in the cylinder 6. Since the intake passage 8 is provided at the end of the independent intake pipe 4, it does not obstruct the main airflow. The opening 30 on the upstream side of the intake passage 8 opens to a collector upstream of the independent intake pipe 4.

FIG. 13 shows a seventh embodiment. FIG. 13 is an example in which two intake passages 8 are configured in parallel. In this way, a vertical swirling flow is reliably formed without collision of the air flow in the cylinder 6.

FIG. 14 shows an eighth embodiment, in which one of the intake passages 8a is configured to inject fuel aiming at the inside of the intake valve 5a, and the other intake passage 8b is connected to the intake valve 5b. It is configured to inject fuel aiming at the outside. Thereby, a horizontal swirling flow can be formed in the cylinder 6. Further, an inclined swirling flow can be formed in the cylinder 6 by inclining the intake passages 8a and 8b in a direction perpendicular to the plane of the drawing.

FIG. 15 shows a ninth embodiment in which the intake passage 8
Both a and 8b are configured to inject fuel aiming outside the intake valves 5a and 5b, respectively. Thereby, a double swirling flow can be formed in the cylinder 6.

FIG. 16 shows a tenth embodiment in which the intake passage 8
“a” is configured to inject fuel aimed at the outside of the intake valve 5b and the intake passage 8b is configured to inject fuel aimed at the outside of the intake valve 5b. This is for forming a horizontal or oblique swirling flow in the cylinder. By selecting the direction of the intake passage 8 as described above, a desired swirling flow can be formed in the cylinder 6. FIGS. 17 to 19 show examples of the independent intake pipe 4 viewed from the side, and show an embodiment in which an auxiliary valve for giving a bias to intake air is used in the independent intake pipe 4. The shape seen from the front of the auxiliary valve is also shown in the upper part of the figure.

FIG. 17 shows an eleventh embodiment in which the auxiliary valve 4 is used.
The lower part of 0 is notched and the air is deflected through this notch 41. However, due to the high speed of the deflected air flow, the fuel spray 43 from the fuel injection valve 10 is deflected and adheres to the wall surface 44. Therefore, the auxiliary valve 40
A notch 42 is provided in the upper part of the nozzle, and an air flow 45 for correcting the fuel spray direction flows to prevent the fuel spray 43 from bending.

FIG. 18 shows a twelfth embodiment in which a partition wall 46 is provided in the independent intake pipe 4 and an auxiliary valve 47 is provided above the partition wall. The high-speed airflow for the intake air drift flows under the partition wall 46 and collides with the fuel spray 43 near the intake valve 5, so that the fuel spray 43 is not deflected.

FIG. 19 shows a thirteenth embodiment in which the auxiliary valve 4
The fuel spray 43 from the fuel injection valve 10 collides with the lower portion 49 of the nozzle 8 to atomize it. in this way,
If the fuel is atomized, even if it is deflected, the fuel flows into the combustion chamber together with the intake air without adhering to the wall surface in the independent intake pipe 4.

FIGS. 20 to 22 show another embodiment in which an auxiliary valve is provided in the independent intake pipe 4 when the independent intake pipe 4 is viewed from the side.

FIG. 20 shows a fourteenth embodiment in which the auxiliary valve 5 is used.
A part of 0 is cut out to give a drift to the intake air. Further, a high-speed airflow 52 is supplied to the deflected high-speed airflow from the intake passage 51 on the side opposite to the fuel spray 43. The high-speed air flow 52 can prevent the fuel spray 43 from being deflected. This high velocity air flow 52 can be obtained by a passage bypassing the throttle valve or auxiliary valve 50.

FIG. 21 shows a fifteenth embodiment in which a partition wall 54 is provided in the independent intake pipe 4, and an auxiliary valve 53 is provided below the partition wall 54.
The upper part was configured so that the air flow 55 flows. At this time, since the air flow 55 collides with the fuel spray 43 near the intake valve 5, the fuel spray 43 is not deflected.

FIG. 22 shows a sixteenth embodiment in which the auxiliary valve 5 is used.
6 has a notch at a position corresponding to the passing position of the fuel spray 43.
7 was provided. Since the fuel spray 43 and the high-speed drift air flow pass through the notch 57 together, the fuel spray 43 flies in the same direction as the air flow without being deflected. By setting the flight direction of the air flow and the fuel spray 43 to a desired position of the intake valve 5, it is possible to obtain a good air-fuel mixture distribution while forming a swirl flow in the cylinder.

Although FIGS. 17, 19, 20, and 22 show the configuration in which the notch portion of the auxiliary valve is provided in the lower portion, a configuration in which a notch is provided in the upper portion of the auxiliary valve may be used. Also,
In FIG. 17, a notch may be provided in the upper part, and a notch for creating an airflow for preventing fuel spray deflection may be provided in the lower part. In FIG. 19, the notch of the auxiliary valve may be provided at the upper part, and the fuel spray may collide with the upper end to atomize. FIG.
In the case of 0, a notch may be provided in the upper portion, and a passage for creating an air flow for fuel spray correction may be supplied from the lower portion. Further, FIG.
Then, a notch may be provided in the upper part of the auxiliary valve. further,
17 to 22 show the case where the fuel spray from the fuel injection valve is in two directions, but in the case of one-way fuel spray, the same effect can be obtained with a similar configuration.

[0033]

According to the present invention, the two intake passages are formed as straight passages having one end opening to the collector and the other end opening to both sides of the fuel injection valve nozzle of the independent intake pipe. Is easy to form.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of the present invention, and is a configuration diagram of an entire intake system.

FIG. 2 is a configuration diagram of an intake pipe of FIG. 1;

FIG. 3 shows a second embodiment of the present invention and is a configuration diagram of an intake passage of a V-type engine.

FIG. 4 is a view taken in the direction of the arrow (b) in FIG. 3;

FIG. 5 shows a third embodiment of the present invention, and is a configuration diagram of an entire intake system.

FIG. 6 shows a fourth embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from above.

FIG. 7 is a longitudinal sectional view of FIG. 6;

FIG. 8 shows a fifth embodiment of the present invention, and is a configuration diagram of an intake pipe.

FIG. 9 is a front view of an auxiliary valve.

FIG. 10 is a map diagram of an air-fuel ratio for engine control.

FIG. 11 is a map diagram of an opening degree of an auxiliary valve for engine control.

FIG. 12 shows a sixth embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from above.

FIG. 13 shows a seventh embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from above.

FIG. 14 shows an eighth embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from above.

FIG. 15 shows a ninth embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from above.

FIG. 16 is a view showing the configuration of an intake pipe viewed from above according to a tenth embodiment of the present invention.

FIG. 17 shows the eleventh embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from a side.

FIG. 18 shows a twelfth embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from a side.

FIG. 19 shows a thirteenth embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from a side.

FIG. 20 shows a fourteenth embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from the side.

FIG. 21 is a side view showing the configuration of an intake pipe according to a fifteenth embodiment of the present invention.

FIG. 22 shows the sixteenth embodiment of the present invention, and is a configuration diagram of an intake pipe viewed from a side.

[Explanation of symbols]

1 ... Throttle valve, 3a, 3b ... Collector, 4 ... Independent intake pipe,
5 ... intake valve, 6 ... cylinder, 7, 29, 40, 47, 4
8, 50, 53, 56: auxiliary valve, 8, 8a, 8b: intake passage, 9: swirl flow, 10: fuel injection valve, 11: fuel spray, 12: air flow.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02M 69/04 F02M 35/10 102R 69/00 350A 350W (72) Inventor Ryoichi Furumuro Omika, Hitachi City, Ibaraki Prefecture 7-1-1, Cho, Hitachi, Ltd. Hitachi Research Laboratory, Ltd. (72) Inventor Masayoshi Momono 2520 Kataida, Ibaraki Pref. AD06 AF01 AG02

Claims (7)

[Claims] A plurality of independent intake pipes connected to an intake valve at an inlet of a combustion chamber of the internal combustion engine for introducing air into the combustion chamber of the internal combustion engine; and the air connected to and introduced to the independent intake pipe. A fuel injection valve installed on a wall surface of the independent intake pipe to supply fuel, an auxiliary valve provided on the independent intake pipe and closed in a specific operation state of an engine, and one end provided to the collector. An internal combustion engine having two intake passages which are opened and bypass the auxiliary valve and are formed at the other end with straight passages open to the independent intake pipe passage portion on both sides of the injection port of the fuel injection valve. Engine intake device. 2. The independent intake pipe according to claim 1, wherein a distance between an upstream opening and a downstream opening of the two intake passages installed in the independent intake pipe is an upstream side of the independent intake pipe. An intake device for an internal combustion engine that is substantially equal to the distance between the opening and the downstream opening. 3. An intake system for an internal combustion engine according to claim 1, wherein the flow of air ejected from said two intake passages and the flow of fuel ejected from said fuel injection valve are substantially parallel. 4. A flow according to claim 1, wherein a flow of air ejected from said two intake passages and a flow of fuel ejected from said fuel injection valve collide on a surface of an intake valve of said internal combustion engine. Intake device for an internal combustion engine. 5. The collector according to claim 1, wherein an upstream opening of said two intake passages is open to a downstream opening of said two intake passages and said independent intake pipe is connected thereto. An intake device for an internal combustion engine that is open to the inside. 6. An intake device for an internal combustion engine according to claim 1, wherein an opening degree of said auxiliary valve is changed according to an operation state of said internal combustion engine. 7. An intake system for an internal combustion engine according to claim 1, wherein said two intake passages bypassing said auxiliary valve are straight passages penetrating an intake passage wall forming said independent intake pipe.