JP2000045880A - Intake manifold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intake manifold in an engine incorporating an EGR gas passage for introducing EGR gas into intake air, which can uniformly supply EGR gas among engine cylinders while the EGR gas is sufficiently mixed with the intake air so as to enhance the exhaust performance. SOLUTION: In an intake manifold 1 having an EGR gas introduction port 9 for introducing EGR gas into intake air, a mixing chamber 4 formed therein with an intake air inlet port 7 and the EGR gas introduction port 9 is communicated thereto with a collector part 2 formed therein a plurality of ports 3 connected to engine cylinders, through a communication port 6, and a throttle valve attaching part 11 and the EGR gas introduction port 9 are arranged so that the center axis P of a throttle valve 12 and the center axis O of the EGR gas introduction port 9 are substantially in parallel with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an intake manifold for an engine, and more particularly to an intake manifold having an EGR gas inlet for introducing EGR gas.

[0002]

2. Description of the Related Art As a conventional intake manifold in which EGR gas is introduced into intake air, for example, Japanese Utility Model Laid-Open No. 3-73649 discloses an intake manifold having a plurality of connection ports formed in each cylinder. In addition, the partition plate defines an EGR gas introduction space along the parallel direction of the connection ports, and the partition plate is provided with an EGR gas distribution hole,
A system in which fresh air and EGR gas are mixed at a collector and supplied to a cylinder is disclosed.

However, in such a configuration, since the EGR gas is dispersedly supplied and mixed in the collector section in which the intake air flows toward each connection port, the intake air of the mixed gas supplied to each cylinder is mixed with the EGR gas. There is a problem that it is difficult to make the mixing amount of the EGR gas uniform and that the mixing of the intake air and the EGR gas is not sufficiently performed.

[0004] Therefore, as shown in FIG. 2, a collector section 22 having a plurality of connection ports connected to each cylinder in an intake manifold 21 and a mixing chamber 24 communicating with the collector section 22 through a communication port 26. And the mixing chamber 24
Is provided with a suction air inlet 27 and an EGR gas introduction port 29 so that the suction air and the EGR gas are sufficiently mixed in the mixing chamber 24 and then flow into the collector section 22 through the communication port 26.

More specifically, the communication port 2 of the mixing chamber 24
The EGR gas inlet 2 is located at the center of the end wall 28 opposite to
9 is provided, and an intake air inlet 27 is formed in one side wall of the mixing chamber 24. A throttle valve 32 is disposed on the outer surface of the intake air inlet 27 with its axis P oriented in a direction orthogonal to the longitudinal axis O of the mixing chamber 24, and a gap between the throttle valve 32 and the venturi cylinder 31 is provided. The intake air passing through the end wall 2 where the EGR gas inlet 29 is disposed
8 is configured to flow into the front part.

[0006]

However, in the above configuration, the intake air flowing into the mixing chamber 24 from the intake air inlet 27 through the space between the venturi cylinder 31 and the throttle valve 32 is indicated by a white arrow. As shown, the intake air inlet 27
The EGR gas introduced into the mixing chamber 24 from the EGR gas inlet 29 passes through the space between the opposite wall and the central portion of the mixing chamber 24, while the EGR gas introduced into the mixing chamber 24 as shown by the arrow. There is a characteristic of flowing along the side wall along the wall, and the mixing effect of the intake air and the EGR gas in the mixing chamber 24 cannot be sufficiently obtained, so that the exhaust gas performance varies greatly between cylinders and the exhaust gas performance of the entire engine is improved. There was a problem that can not be expected.

The present invention has been made in view of the above-mentioned conventional problems, and provides an intake manifold capable of sufficiently mixing EGR gas with intake air and supplying the mixed gas to each cylinder, thereby improving exhaust gas performance. Aim.

[0008]

SUMMARY OF THE INVENTION An intake manifold according to the present invention is an EGR system for introducing EGR gas into intake air.
An intake manifold having a gas inlet,
A mixing chamber having an intake air inlet and an EGR gas inlet formed therein so as to be communicated through a communication port to a collector portion having a plurality of connection ports connected to each cylinder; The axis of the throttle valve arranged at the inlet and E
The throttle valve mounting portion and the EGR inlet are disposed such that the axis of the GR gas inlet is substantially parallel to the axis. The intake air flowing into the mixing chamber from the throttle valve through the intake air inlet is provided. A swirling flow is formed around the central axis in the longitudinal direction of the mixing chamber, and a negative pressure region is formed at the center of the swirling flow. The EGR introduced from the EGR gas inlet is sucked and mixed, and the EGR gas flowing along the wall surface also swirls. Therefore, the EGR gas can be supplied to each cylinder in a state where the EGR gas is sufficiently mixed with the intake air, the exhaust gas performance of each cylinder can be made uniform, and the overall engine performance can be improved. Exhaust gas performance can be improved.

Further, when the EGR gas inlet is disposed near the side wall of the mixing chamber, the intake air and the EGR gas collide with each other more reliably, and the EGR gas is more sufficiently mixed to exhibit a greater effect.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG.

In FIG. 1, reference numeral 1 denotes an intake manifold mounted on a four-cylinder engine of an automobile, and four connection ports 3 for each cylinder are formed in parallel on one side of a horizontally long collector part 2. A mixing chamber 4 having an appropriate length of about one half to one third of the collector part 2 is provided integrally from a substantially central part on the other side of the collector part 2 toward one end in the longitudinal direction. Among the side walls 5 of the mixing chamber 4, the partition 5 a separating the mixing chamber 4 and the collector 2 has a collector 2.
A communication port 6 is opened at a substantially central portion of the mixing chamber 4, and the mixing chamber 4 and the collector section 2 communicate with each other.

An intake air inlet 7 for introducing intake air into the mixing chamber 4 is formed on the upper surface of one end of the mixing chamber 4 remote from the communication port 6. An EGR gas inlet 9 for introducing EGR gas is formed in an end wall 8 of the mixing chamber 4 remote from the communication port 6.
The gas introduction pipe 10 is integrally formed so as to protrude.

A throttle valve mounting portion 11 is formed above the intake air inlet 6, and the throttle valve mounting portion 11 has an EGR gas inlet port whose axis P of the throttle valve 12 is parallel to the longitudinal direction of the mixing chamber 4. The shaft 9 is configured to be parallel to the axis O. Further, the EGR gas inlet 9 is disposed so as to be displaced downward so as to be located not near the center of the mixing chamber 4 but near the side wall 5. Specifically, EG
The distance between the axis O of the R gas inlet 9 and the side wall 5 is 1.5 times or less the radius of the EGR gas inlet 9, preferably 1.1 to 1.5 times.
It is arranged at a position about 1.3 times.

Next, the operation of the intake manifold 1 having the above configuration will be described. The intake air flowing into the mixing chamber 4 through the intake air inlet 7 from the throttle valve 12 opened at an arbitrary opening is mixed as shown by a white arrow in FIGS. 1 (a) and 1 (b). After flowing downward along the partition wall portion 5a of the side wall 5 of the chamber 4, it is swirled along the side wall as it is, and becomes a swirling flow around the longitudinal central axis of the mixing chamber 4 to form the communication port 6.
Flows towards Therefore, a negative pressure region is formed at the center of the swirling flow, and E is introduced from EGR gas inlet 9.
The GR gas is sucked and entrained and mixed in the swirling flow of the intake air, and the EGR gas flowing along the side wall 5 of the mixing chamber 4 also collide with the swirling intake air and is effectively mixed. Further, since the EGR gas inlet 9 is disposed near the side wall 5 of the mixing chamber 4, the swirling intake air and the EGR gas flowing along the side wall 5 of the mixing chamber 4 more reliably collide with each other. Mixed. Thus, the intake air is in a state where the EGR gas is sufficiently mixed in the mixing chamber 4, and the intake air in which the EGR gas is uniformly dispersed and mixed flows into the collector 2 through the communication port 6.

EG flowing into the substantially central portion of the collector portion 2
The intake air in which the R gas is evenly mixed is uniformly distributed to each connection port 3 by the collector section 2 and supplied to the corresponding cylinder. Therefore, the intake air can be supplied to each cylinder in a state where the EGR gas is sufficiently mixed, the exhaust gas performance of each cylinder can be made uniform, and the exhaust gas performance of the entire engine can be improved.

[0016]

According to the intake manifold of the present invention, the mixing chamber in which the intake air inlet and the EGR gas inlet are formed as described above is provided. Since the throttle valve mounting portion and the EGR introduction port are arranged so that the axis of the EGR gas introduction port is substantially parallel, the intake air flowing into the mixing chamber from the throttle valve through the intake air inlet is mixed. A suction flow is formed around the central axis in the longitudinal direction, a negative pressure region is formed in the center of the swirl flow, and the EGR introduced from the EGR gas inlet is sucked and mixed, and the EGR gas flowing along the wall surface also swirls. The air is effectively mixed with the air, so that the EGR gas can be supplied to each cylinder in a state of being sufficiently mixed with the intake air, and the exhaust gas performance of each cylinder can be made uniform. , It is possible to improve the overall engine exhaust gas performance.

Further, when the EGR gas inlet is disposed near the side wall of the mixing chamber, the intake air and the EGR gas collide with each other more reliably, and the EGR gas is more sufficiently mixed to exhibit a greater effect.

[Brief description of the drawings]

1A and 1B show an intake manifold according to an embodiment of the present invention, wherein FIG. 1A is a plan view partially cross-sectionally shown, and FIG. 1B is a cross-sectional side view taken along line AA of FIG.

FIG. 2 shows a conventional intake manifold;
(A) is a partial vertical cross-sectional view, (b) is a cross-sectional view taken along the line BB of (a).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Intake manifold 2 Collector part 3 Connection port 4 Mixing chamber 5 Side wall 6 Communication port 7 Intake air inlet 9 EGR gas introduction port 11 Throttle valve attachment part 12 Throttle valve Axis of EGR gas introduction port 9 P Axis of throttle valve 12

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Keita Nishikawa 2-1-1 Taoyuan, Ikeda-shi, Osaka Daihatsu Industry Co., Ltd. (72) Inventor Takashi Tachikawa 1-Toyota-cho, Toyota-shi, Aichi Prefecture Toyota Motor Corporation F term in the company (reference) 3G062 AA03 BA06 EA06 ED04 ED15

Claims (2)

[Claims] An EG for introducing EGR gas into intake air
An intake manifold having an R gas inlet, wherein an intake air inlet and an EGR gas inlet are connected through a communication port to a collector portion having a plurality of connection ports connected to each cylinder. Is provided, and the axis of the throttle valve disposed at the intake air inlet and the axis of the EGR gas inlet are substantially parallel to each other.
An intake manifold having a throttle valve mounting portion and an EGR inlet. 2. The intake manifold according to claim 1, wherein the EGR gas inlet is disposed near a side wall of the mixing chamber.