JP2020090923A - Intake manifold - Google Patents

Abstract

To suppress the hindrance of good engine operation due to the flow of gas other than atmospheric air introduced into a surge tank in eccentricity to intake ports of cylinders.SOLUTION: An intake manifold 1 includes a surge tank 6 formed with a fresh air introduction port 6a linked to atmospheric air via a throttle body and a plurality of delivery ports 11-13 linked to the intake ports of the cylinders of an internal combustion engine via suction pipe parts 7-9, respectively. The surge tank 6 has a gas introduction port 14 formed in an area between the fresh air introduction port 6a and each of the delivery ports 11-13. In areas between the gas introduction port 14 and each of the delivery ports 11-13, guide walls 15, 16 are formed to guide blow-by gas introduced from the gas introduction port 14 to flow to the delivery ports 11-13, respectively. A partition wall 18 extending to be bridged to the guide walls 15, 16 is provided therebetween so as to partition the gas introduction port 14 and the fresh air introduction port 6a.SELECTED DRAWING: Figure 3

Description

The present invention relates to an intake manifold.

The intake manifold provided in the intake system of the internal combustion engine includes a fresh air introduction port that is connected to the atmosphere through the throttle body, and a plurality of guides that are connected to the intake ports of each cylinder in the internal combustion engine through intake pipe sections. It has a surge tank with an outlet. During operation of the internal combustion engine, the atmosphere (air) flows from the throttle body into the surge tank through the fresh air inlet, passes through the surge tank, and then passes through the outlets through the intake pipe section. Are distributed to the intake ports of each cylinder.

The intake air amount during operation of the internal combustion engine, that is, the flow rate of air flowing into the intake port of each cylinder in the internal combustion engine can be adjusted by changing the opening degree of the throttle valve provided in the throttle body. ing. Various sensors are provided near the throttle valve, for example, a sensor such as a pressure sensor that detects the pressure on the downstream side of the throttle valve in the air flow direction.

In the surge tank of the intake manifold, a gas introduction port for introducing a gas other than the atmosphere, for example, a blow-by gas, is formed in the surge tank between the fresh air introduction port and the discharge port. By introducing the blow-by gas into the surge tank through the gas introduction port, the blow-by gas flows into the intake port together with air and is processed by the internal combustion engine.

It should be noted that in Patent Document 1, in order to prevent the blow-by gas introduced into the surge tank through the gas introduction port from flowing back to the throttle body side, it flows backward to a portion between the gas introduction port and the fresh air introduction port in the surge tank. It is described that a preventive wall (backflow restricting portion) is formed. By preventing blow-by gas from flowing back to the throttle body side by such walls, it is possible to prevent the blow-by gas from polluting the throttle valve, the sensor and the like.

JP, 2018-91310, A

By the way, when introducing blow-by gas into the surge tank, if the amount of blow-by gas flowing into the intake port of each cylinder becomes uneven, the air-fuel ratio of each cylinder also becomes uneven and adversely affects engine operation. .. Incidentally, since Patent Document 1 does not disclose anything about controlling the flow of the blow-by gas introduced into the surge tank to the intake port, even if the technique of Patent Document 1 is used, It is not possible to prevent the amount of blow-by gas flowing into the intake port from becoming uneven.

SUMMARY OF THE INVENTION An object of the present invention is to provide an intake manifold that can prevent a favorable engine operation from being hindered by gas other than the air introduced into the surge tank being biased toward the intake port of each cylinder.

Hereinafter, the means for solving the above problems and the effects thereof will be described.
An intake manifold that solves the above problems is provided with a fresh air intake port that is connected to the atmosphere through a throttle body, and a plurality of outlet ports that are connected to the intake ports of each cylinder in an internal combustion engine through intake pipe portions. Equipped with a surge tank. A gas inlet for introducing a gas other than the atmosphere into the surge tank is formed between the fresh air inlet and outlet in the surge tank. A backflow restricting portion is provided between the air inlet and the air inlet. Further, a guide wall for guiding the gas introduced from the gas inlet to the plurality of outlets is provided in a portion between the gas inlet and the outlet in the surge tank.

According to the above configuration, when a gas other than the atmosphere is introduced into the surge tank through the gas introduction port, the reverse flow of the gas toward the fresh air introduction port is suppressed by the backflow regulating unit. The gas introduced into the surge tank is guided by the guide wall so as to flow toward the plurality of outlets, so that the amount of the gas flowing into the intake port of each cylinder in the internal combustion engine is not biased. Suppressed. Therefore, it is possible to prevent the favorable engine operation from being hindered due to the gas flowing unevenly with respect to the intake port of each cylinder.

FIG. 3 is a perspective view showing a state in which the intake manifold is viewed from an intake side of a cylinder head in an internal combustion engine. The side view which shows the state which looked at the intake manifold from the arrow A direction of FIG. Sectional drawing which shows the state which looked at the surge tank of an intake manifold from the arrow BB direction of FIG. FIG. 3 is a perspective view showing a peripheral structure of an outlet and a gas inlet in the surge tank.

An embodiment of the intake manifold will be described below with reference to FIGS.
FIG. 1 shows a state in which an intake manifold 1 provided in an intake system of an internal combustion engine is viewed from the intake side (intake port side) of a cylinder head in the same engine. The intake manifold 1 is formed by connecting resin-made divided bodies 2 to 5 which are vertically stacked to each other by vibration welding or the like.

The intake manifold 1 is provided with a surge tank 6 having a fresh air introduction port 6a. A throttle body having a throttle valve is connected to the fresh air introduction port 6a of the surge tank 6. The fresh air introduction port 6a of the surge tank 6 is connected to the atmosphere via the throttle body and the like. In the throttle body, a sensor such as a pressure sensor is provided at a portion closer to the fresh air introduction port 6a of the surge tank 6 than the throttle valve.

FIG. 2 shows a state in which the intake manifold 1 of FIG. 1 is viewed from the direction of arrow A. As shown in FIGS. 1 and 2, the intake manifold 1 is provided with a plurality of intake pipe portions 7 to 9 corresponding to each cylinder of the internal combustion engine. One end of each of the intake pipe portions 7 to 9 is connected to the surge tank 6. Further, a flange portion 10 for attaching the intake manifold 1 to the intake side of the cylinder head of the internal combustion engine is formed at the other ends of the intake pipe portions 7 to 9.

As shown in FIG. 1, openings 10a to 9a on one end side of the intake pipe portions 7 to 9 are opened on a surface 10a of the flange portion 10 on the intake side of the cylinder head. Then, the intake manifold 1 is attached to the intake side of the cylinder head by bolting the flange portion 10 to the intake side of the cylinder head. At this time, the openings 7a to 9a of the intake pipe portions 7 to 9 are respectively connected to the intake ports connected to the combustion chambers of the cylinders of the internal combustion engine.

FIG. 3 shows a state where the surge tank 6 of the intake manifold 1 of FIG. 2 is viewed from the direction of arrow BB. As can be seen from FIG. 3, in the portion where the intake pipe portions 7 to 9 of the surge tank 6 are connected, outlet ports 11 to 13 which are connected to the intake ports of each cylinder of the internal combustion engine through the intake pipe portions 7 to 9 are formed. Has been done. In other words, the ends of the intake pipes 7 to 9 on the surge tank 6 side are connected to the outlets 11 to 13 of the surge tank 6, respectively.

At the time of operation of the internal combustion engine, the atmosphere (air) flows from the throttle body into the surge tank 6 through the fresh air inlet port 6a, passes through the surge tank 6, and then from the plurality of outlet ports 11 to 13 to the intake pipe portion 7. Through 9 are distributed to the intake ports of each cylinder in the internal combustion engine. The intake air amount during operation of the internal combustion engine, that is, the flow rate of the air flowing into the intake port of each cylinder in the internal combustion engine is adjusted by changing the opening degree of the throttle valve provided in the throttle body.

Next, the internal structure of the surge tank 6 will be described in detail.
In the surge tank 6, a gas introduction port 14 for introducing a gas other than the atmosphere, for example, a blow-by gas, into the surge tank 6 is formed in a portion between the fresh air introduction port 6a and the discharge ports 11 to 13. ing. Then, the blow-by gas is introduced into the surge tank 6 through the gas introduction port 14, so that the blow-by gas flows into the intake port together with air and is processed by the internal combustion engine.

The fresh air introduction port 6a is formed in the upper portion of the surge tank 6 in FIG. 3 and opens downward. On the other hand, the outlets 11 to 13 are formed in the lower portion of the surge tank 6 in FIG. 3 and are open upward. Therefore, the fresh air inlet port 6a and the outlet port 11 are open in the direction in which they face each other. The plurality of outlets 11 to 13 are formed in the surge tank 6 so as to be parallel to each other in the left-right direction in FIG. Furthermore, the gas inlet port 14 is located between the fresh air inlet port 6a and the outlet ports 11 to 13 of the surge tank 6 and in the direction in which the plurality of outlet ports 11 to 13 are arranged (see FIG. 3). It is formed in the surge tank 6 so as to be positioned corresponding to the central portion in the left-right direction).

A guide for guiding the blow-by gas introduced from the gas inlet 14 toward the plurality of outlets 11 to 13, respectively, in a portion of the surge tank 6 between the gas inlet 14 and the outlets 11 to 13. Walls 15 and 16 are formed. The guide wall 15 is provided so as to be positioned between the adjacent outlets 11 to 13 of the plurality of outlets 13, respectively. The guide wall 16 is provided outside the outermost outlets 11 and 13 in the arrangement direction of the outlets 11 to 13 in the arrangement direction.

FIG. 4 shows the vicinity of the outlets 11 to 13 and the gas inlet 14 in the surge tank 6. As can be seen from FIG. 4, the guide wall 16 extends from the vicinity of the outlets 11 and 13 to the vicinity of the gas inlet 14. A diffusion space 17 for diffusing the blow-by gas introduced from the gas introduction port 14 is a portion sandwiched between the guide walls 16 and between the gas introduction port 14 and the guide wall 15. Exists. Further, a partition wall 18 is formed integrally with the upper ends of the plurality of guide walls 15 and 16 so as to extend over the guide walls 15 and 16. As shown in FIG. 3, the partition wall 18 is provided between the gas introduction port 14 and the fresh air introduction port 6 a so as to partition it, and the blow-by introduced into the surge tank 6 from the gas introduction port 14. It plays a role as a backflow control unit that controls the backflow of gas to the fresh air inlet port 6a.

Next, the function and effect of the intake manifold 1 in this embodiment will be described.
(1) When the blow-by gas is introduced into the surge tank 6 through the gas introduction port 14, the partition 18 prevents the blow-by gas from flowing back toward the fresh air introduction port 6a. By preventing the blow-by gas from flowing backward to the fresh air introduction port 6a side (throttle body side) by the partition wall 18 in this manner, it is possible to prevent the blow-by gas from polluting the throttle valve and the sensor. The blow-by gas introduced into the surge tank 6 is guided by the guide walls 15 and 16 so as to flow toward the plurality of outlets 11 to 13, respectively. As a result, it is possible to prevent the amount of the blow-by gas flowing into the intake port of each cylinder in the internal combustion engine from being unbalanced. Therefore, it is possible to prevent the good engine operation from being disturbed due to the blow-by gas unevenly flowing with respect to the intake port of each cylinder.

(2) In the intake manifold 1, the fresh air inlet port 6a and the outlet ports 11 to 13 are open in the direction in which they face each other. For this reason, if the distance from the fresh air inlet 6a to the outlets 11 to 13 is short, the blow-by gas introduced into the surge tank 6 from the gas inlet 14 easily flows back toward the fresh air inlet 6a. However, it is possible to guide the blow-by gas toward the plurality of outlets 11 to 13 by the guide walls 15 and 16 while suppressing such backflow by the partition wall 18.

(3) In the intake manifold 1, the plurality of outlets 11 to 13 are formed in the surge tank 6 in parallel. Further, the gas inlet port 14 is formed in the surge tank 6 so as to be located corresponding to the central portion of the plurality of outlet ports 11-13 in the direction in which they are arranged. Therefore, it becomes easy to form the guide walls 15 and 16 so that the blow-by gas that has flowed into the surge tank 6 from the gas inlet 14 flows toward the plurality of outlets 11 to 13, respectively.

(4) The guide wall 15 is provided between the adjacent outlets 11 to 13 in the plurality of outlets 11 to 13, and the guide wall 16 is the outermost guide in the arrangement direction of the outlets 11 to 13. It is provided outside the outlets 11 and 13 in the above-mentioned arrangement direction. Therefore, the gas flowing into the surge tank 6 from the gas introduction port 14 can be made to flow toward the plurality of outlet ports 11 to 13 through the portion between the guide walls 15 and 16, respectively.

(5) In the intake manifold 1, a portion of the surge tank 6 between the gas inlet 14 and the guide wall 15 has a diffusion space 17 for diffusing the blow-by gas introduced from the gas inlet 14. ing. Therefore, the blow-by gas flowing into the surge tank 6 from the gas inlet 14 diffuses in the diffusion space 17 and then flows toward the plurality of outlets 11 to 13, respectively. Therefore, the amount of the blow-by gas flowing into the intake port of each cylinder in the internal combustion engine is less likely to be biased.

(6) The partition wall 18 extends so as to partition the gas introduction port 14 and the fresh air introduction port 6a and to be bridged by the plurality of guide walls 15 and 16. Therefore, the partition wall 18 not only suppresses the reverse flow of the blow-by gas introduced into the surge tank 6 from the gas introduction port 14 toward the fresh air introduction port 6a, but also allows the blow-by gas to be discharged into the plurality of discharge ports 11a. It will also play a role of guiding the flow toward ~13.

The above embodiment can be modified as follows, for example.
The backflow regulating portion does not necessarily have to be realized by the partition wall 18. For example, the partition wall 18 may be omitted and a backflow regulating portion different from the partition wall 18 may be provided.

The guide walls for guiding the gas introduced from the gas introduction port 14 into the surge tank 6 toward the plurality of discharge ports 11 to 13 are not necessarily formed in the manner of the guide walls 15 and 16. You don't have to be.

-The gas inlet port 14 does not necessarily need to be formed so as to correspond to the central portion of the outlet ports 11 to 13 in the direction in which they are arranged.
-The outlets 11 to 13 do not necessarily have to be formed in parallel.

-The fresh air inlet port 6a and the outlet ports 11 to 13 do not necessarily have to open in the direction in which they face each other.
The gas other than the air introduced into the surge tank 6 from the gas introduction port 14 does not necessarily have to be blow-by gas, and may be gas such as EGR gas or purge gas.

1... Intake manifold, 2... Divided body, 3... Divided body, 4... Divided body, 5... Divided body, 6... Surge tank, 6a... Fresh air introduction port, 7... Intake pipe part, 7a... Opening part, 8... Intake pipe part, 8a... Opening part, 9... Intake pipe part, 9a... Opening part, 10... Flange part, 10a... Surface, 11... Outlet port, 12... Outlet port, 13... Outlet port, 14... Gas inlet port, 15... Guide wall, 16... Guide wall, 17... Diffusion space, 18... Partition wall.

Claims (6)

A fresh air inlet connected to the atmosphere via the throttle body, and a surge tank having a plurality of outlets connected to the intake ports of each cylinder of the internal combustion engine via intake pipes are provided. A gas inlet for introducing a gas other than the atmosphere into the surge tank is formed in a portion of the surge tank between the fresh air inlet and the outlet, and the gas inlet in the surge tank is formed. In an intake manifold provided with a backflow restricting portion in a portion between the fresh air inlet and
A portion of the surge tank between the gas inlet and the outlet is provided with a guide wall for guiding the gas introduced from the gas inlet toward the outlets. Intake manifold characterized by The intake manifold according to claim 1, wherein the fresh air inlet port and the outlet port are opened in a direction in which they face each other. The plurality of outlets are formed in the surge tank so as to be in parallel,
The intake manifold according to claim 1 or 2, wherein the gas inlet is formed in the surge tank so as to be located at a central portion of the plurality of outlets in a direction in which they are arranged. The guide wall is provided between adjacent outlets in the plurality of outlets, and is also provided outside the outlet in the alignment direction with respect to the outermost outlet in the alignment of the outlets. Item 4. The intake manifold according to item 3. The intake manifold according to claim 4, wherein a diffusion space for diffusing a gas introduced from the gas introduction port is present in a portion of the surge tank between the gas introduction port and the guide wall. The intake manifold according to claim 4 or 5, wherein the backflow restricting portion is a partition wall that extends so as to divide the gas introduction port and the fresh air introduction port and to be bridged by the plurality of guide walls. ..