JPS63314358A - Intake manifold for internal combustion engine - Google Patents

Abstract

PURPOSE:To make the engine compact by connecting a common suction chamber through independent suction passages to suction ports of cylinders, and inclining an axis of a suction inlet formed at one end of the suction chamber with respect to an axis of the suction chamber. CONSTITUTION:An intake manifold 11 in a three-cylinder internal combustion engine 10 is constructed of a chamber 12 extending in parallel to an axis 10a of a crankshaft and independent suction passages 16-18 connecting the chamber 12 to suction ports 13-15, respectively. A throttle body 20 is connected to a suction inlet 19 formed at one end of the chamber 12. An axis 19a of the suction inlet 19 is inclined at a suitable angle theta in a direction approaching to the internal combustion engine 10 with respect to an axis 12a of the chamber 12. Further, an inner wall of the chamber 12 at a portion where a suction air from the suction inlet 19 collides is formed with an arcuately recessed guide surface 24 for curving the flow of the suction air to the center of the chamber 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in an intake manifold that distributes intake air to each cylinder in a multi-cylinder internal combustion engine.

[Conventional technology and its problems]

One of the intake manifolds for a multi-cylinder internal combustion engine is a chamber 2 which is described in, for example, Japanese Utility Model Publication No. 59-13334, and which extends parallel to the axis 1a of the crankshaft in the internal combustion engine 1, as shown in FIG. There is one in which the intake port in each cylinder is connected via an intake passage 3 that is independent of each other for each cylinder.

This type of intake manifold is used to perform inertial supercharging on an internal combustion engine, but conventionally, an intake manifold of 4
is shaped so that the axis 4a of the intake port 4 is parallel to the longitudinal axis 2a of the chamber 2, and in the case of a combustion injection type internal combustion engine, the intake port 4 has a built-in throttle valve 5. Install throttle body 6,
When the intake pipe 8 from the air cleaner 7 is connected to the throttle body 6, the substantial total length of the chamber 2 including the throttle body 6 is Lo.
In addition to being longer, the throttle body 6 is
Since it will be located at a location far from the internal combustion engine 1,
The total length of the internal combustion engine in the crankshaft direction and the width in the direction perpendicular to the crankshaft both increase, resulting in a significantly larger internal combustion engine.

The present invention provides an intake air intake system that makes it possible to downsize an internal combustion engine while minimizing increase in intake flow resistance when a throttle body with a throttle valve is attached to one end of a chamber extending in the axial direction of a crankshaft. The purpose is to provide a manifold.

[Means for solving problems]

For this reason, the present invention comprises a chamber extending in the axial direction of the crankshaft in an internal combustion engine, and an intake passage independently connecting the chamber and the intake port of each cylinder; In an intake manifold in which a throttle body with a throttle valve is joined to an intake inlet provided at one end, the axis of the intake inlet is bent at an appropriate angle in the direction approaching the internal combustion engine with respect to the longitudinal direction of the chamber. On the other hand,
The inner wall surface of the chamber is configured such that an arcuate guide surface is recessed in a portion of the inner wall surface of the chamber that is hit by the intake air from the intake inlet to deflect the intake air toward the center of the chamber.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The internal combustion engine 10 is placed horizontally in an engine room (not shown) of an automobile so that the axis 10a of the crankshaft is approximately perpendicular to the direction of travel of the automobile. It is installed.

Reference numeral 11 indicates an intake manifold for the internal combustion engine 10;
0, a chamber 12 extending parallel to the axis 10a of the crankshaft, and a chamber 12 and each cylinder Al, A.
2. It is constituted by intake passages 16, 17, and 18 that are independently connected to the intake ports 13, 14, and 15 at A3. In this case, each intake passage 16
The distance between the connections to the chamber 12 is 17.18° for each cylinder Al, A2. The dimensions are set narrower than the A3 spacing.

An intake population 19 is formed at one end of the chamber 12 in this intake manifold 11.
The throttle body 2 has a built-in throttle valve 21.
0 is connected to this throttle body 20,
An intake pipe 23 from an air cleaner 22 is connected.

Then, the axis 19a of the intake population 19 is bent and inclined at an appropriate angle θ in the direction in which the axis 19a of the intake population 19 approaches the internal combustion engine 10 with respect to the longitudinal axis 12a of the chamber 12.
An arcuate guide surface 24 that deflects the intake air toward the center of the chamber 12 is recessed in a portion of the inner wall surface 12b that is hit by the intake air from the intake port 19.

In this way, the intake population 19 is provided at one end of the chamber 12 extending in the axial direction 10a of the crankshaft, and the intake population 1
9, when installing the throttle body 20 with the throttle valve 21, the axis 19a of the intake port 19 is aligned with the longitudinal axis 12a of the chamber 12.
If a is bent and tilted by an appropriate angle θ in the direction toward the internal combustion engine 10, the substantial entire length of the chamber 12 including the throttle body 21 can be changed from the axis of the intake inlet as shown in FIG. Substantially the entire length of the chamber when parallel to the longitudinal axis.

It can be made shorter by the amount of bending and inclination.
Also, from the outermost side of the throttle body 11, the internal combustion engine 1
The distance S to the center of 0 can also be made shorter by the amount of the bending and inclination than the distance SO when the axis of the intake inlet is made parallel to the longitudinal axis of the chamber as shown in FIG. 11 can be brought closer to the internal combustion engine 10.

However, on the other hand, according to the inventor's experiments, when the guide surface 24 is not provided, the axis 19 of the intake population 19
By bending and inclining a with respect to the longitudinal axis 12a of the chamber 12, the flow resistance of the intake air increases, resulting in a decrease in the intake efficiency for each cylinder and, in turn, a decrease in the output of the internal combustion engine 10.

That is, the axis 19a of the intake population 19 is aligned with the chamber 12.
When it is bent and tilted with respect to the longitudinal axis 12a, the intake population 1
The intake air from 9 flows into the chamber 12 in the direction of the arrow A along the axis 19a of the intake population 19, and collides with the inner wall surface 12b of the chamber 12, so that the intake air flows into the chamber 12 in the direction of the arrow B indicated by the chain double-dashed line.
As shown in , the direction is changed along the longitudinal direction of the chamber 12, and when the direction is changed by colliding with the inner wall surface 12b, considerable flow resistance is generated due to energy loss due to the collision. Moreover, this flow resistance becomes larger as the bending angle θ of the intake manifold 19 with respect to the chamber 12 is made larger in order to downsize the internal combustion engine 10.

In contrast, the present invention provides an arc-shaped guide surface that deflects the intake air toward the center of the chamber 12, on the portion of the inner wall surface 12b of the chamber 12 that is hit by the intake air from the intake port 19, as described above. 24 is recessed, and the intake air flowing from the intake port 19 into the chamber 12 in the direction of the arrow A along the direction of the axis 19a is directed by the arc-shaped guide surface 24 to the th direction as shown by the arrow C. Since the collision with the inner wall surface 12b of the chamber 12 can be avoided by being guided by the This makes it possible to reduce the increase in resistance to intake flow.

[Action/effect of the invention]

As described above, according to the present invention, since the axis of the intake inlet at one end of the chamber is inclined with respect to the longitudinal axis of the chamber, when a throttle body is attached to the intake inlet, the state including the throttle body Since the substantial overall length of the chamber can be shortened and the throttle body can be moved closer to the internal combustion engine, it is possible to downsize the internal combustion engine.

On the other hand, an arc-shaped guide surface is recessed in the part of the inner wall surface of the chamber that is hit by the intake from the intake inlet, which deflects the intake air toward the center of the chamber. By making the bend W4 oblique with respect to the longitudinal axis, an increase in intake flow resistance can be avoided.

Therefore, according to the present invention, it is possible to downsize the internal combustion engine without increasing the flow resistance of intake air, and without causing a decrease in output due to the increase in intake flow resistance.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view showing an embodiment of the present invention, FIG. 2 is a sectional view taken along line nn in FIG. 1, and FIG. 3 is a plan view showing a conventional case. 10...Internal combustion engine, IOa...Crank axis,
AI, A2. A3...Cylinder, 11...Intake manifold, 12...Chamber, 12a...Longitudinal axis of chamber, 16.17.18...Intake passage, 19...Intake Inlet, 19a... Axis of intake inlet, 20... Throttle body, 21... Throttle valve, 22... Air cleaner, 23...
Intake pipe line, 24...Guide surface.

Claims (1)

[Claims] (1) Consisting of a chamber extending in the axial direction of the crankshaft in an internal combustion engine, and an intake passage independently connecting the chamber and the intake port of each cylinder, and one longitudinal end of the chamber; In an intake manifold in which a throttle body with a throttle valve is joined to an intake inlet provided in the chamber, the axis of the intake inlet is bent and inclined at an appropriate angle in a direction approaching the internal combustion engine with respect to the longitudinal direction of the chamber; An intake manifold for an internal combustion engine, characterized in that an arcuate guide surface for deflecting intake air toward the center of the chamber is recessed in a portion of the inner wall surface of the chamber that is hit by intake air from the intake inlet.