JP2003042018A - Intake system for engine with turbo charger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively damp intake pulsation generated by a turbo charger without using a special passage or a control valve for an engine having the turbo charger arranged on the right upstream side of a chamber communicating with an inlet passage on a cylinder side. SOLUTION: Air discharged from the turbo charger is guided through a connection passage 6 for an intake manifold 2 into a collector 4, and it is made to collide with and reflected from the upper part of an inner wall face 5a opposite to an opening portion 6a of the connection passage 6 in an inner space 5 of the collector 4 and further made to collide with and reflected from an inner wall face 5b on the opposite side to the inner wall face 5a, whereby it is formed into an air mass with uniform pressure having damped pulsating energy to be equally distributed to each cylinder of an engine. Thus, the intake pulsation from the turbo charger can be damped in a simple structure without using the special passage or the control valve, the intake efficiency be improved to enhance the limit of knocking the engine and output performance and fuel consumption be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake system for an engine with a supercharger in which a supercharger is arranged immediately upstream of a chamber communicating with an intake passage on a cylinder side.

[0002]

2. Description of the Related Art Generally, for a naturally aspirated engine,
With an engine equipped with a mechanical supercharger such as a supercharger, it is possible to achieve higher output by supplying fresh air with a higher density, but when adopting the supercharger, pressure pulsation of the discharge air causes It is important to take measures to prevent noise generation and reduction of intake efficiency.

Therefore, various proposals have conventionally been made to reduce the influence of pressure pulsation of the supercharger. For example, Japanese Patent Laid-Open No. 7-238839 discloses two displacement chambers of a roots type supercharger. The first and second control valves are provided in the first and second communication passages respectively communicating with the discharge side, and the pressure pulsation is reduced by controlling the opening and closing of the first and second control valves to reduce noise. A technique for reducing the above is disclosed.

[0004]

However, in a vehicle having a relatively large degree of freedom in the arrangement of the engine and the intake system, an intake air pulsation is provided by appropriately disposing an intercooler or an air cleaner between the supercharger and the engine. Can be absorbed, which is advantageous in terms of cost without providing a special passage or control valve as in the prior art.

Therefore, although it is desirable to devise the layout of the engine and the intake system to damp the intake pulsation due to the supercharger, a vehicle in which the arrangement of the engine and the intake system is restricted due to the vehicle body structure, for example, a one-box type vehicle. In vehicles with an engine mounted at the rear of the vehicle, there is a case where it is necessary to connect a supercharger directly upstream of the intake manifold due to restrictions on arrangement space and maintenance considerations. The pulsation of intake air generated by the engine may directly pass through the intake manifold to cause a pressure fluctuation that does not match the valve timing, resulting in knocking, ignition failure, or the like.

The present invention has been made in view of the above circumstances, and uses a special passage, control valve, or the like for an engine in which a supercharger is arranged immediately upstream of a chamber communicating with an intake passage on the cylinder side. It is an object of the present invention to provide an intake device for an engine with a supercharger, which can effectively attenuate the intake pulsation generated in the supercharger.

[0007]

In order to achieve the above object, the invention according to claim 1 relates to an engine with a supercharger in which a supercharger is arranged immediately upstream of a chamber communicating with an intake passage on a cylinder side. In the intake device, the passage for guiding the discharge air from the supercharger into the chamber and the intake passage are opened at inner wall surfaces facing each other in the chamber and at positions deviated from each other.

According to a second aspect of the present invention, in the first aspect of the invention, the passage for guiding the discharge air from the supercharger into the chamber is opposed to the inner wall surface of the chamber in an oblique direction. It is characterized by arranging.

That is, according to the first aspect of the present invention, the opening of the passage for guiding the discharge air from the supercharger into the chamber and the opening of the intake passage on the cylinder side are opposed to each other in the chamber. And by arranging them at positions displaced from each other,
The discharge air from the supercharger is reflected on the inner wall surface in the chamber to interfere and attenuate the pulsation, and the pressure is made uniform to be sucked into the cylinder from the intake passage.

At this time, as in the second aspect of the invention, it is desirable that the passage for guiding the discharge air from the supercharger into the chamber is arranged so as to face the inner wall surface of the chamber in an oblique direction. It is possible to reliably reflect the air that has entered the chamber on the inner wall surfaces that face it, and discharge it to the intake passage side.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 relate to an embodiment of the present invention. FIG. 1 is an external view showing an arrangement of an engine and an intake device, and FIG. 2 is a sectional view of a collector.

In FIG. 1, reference numeral 1 is an engine,
In the present embodiment, an in-line 4-cylinder vertical engine is mounted in a relatively narrow space behind the vehicle body of, for example, a one-box type vehicle. An intake manifold 2 communicating with an intake port of each cylinder is attached to a cylinder head of the engine 1, and an intake manifold 2 is connected to an upstream side of the intake manifold 2.
A collector 4 that integrally forms the intake passages 3 for each cylinder and forms a chamber is integrally formed.

Further, due to the restriction of the arrangement space of the engine 1 and the intake system, a mechanical supercharger 10 such as a supercharger driven by the engine 1 is provided via a duct 8 directly upstream of the collector 4 of the intake manifold 2. Directly connected. The intake side of the supercharger 10 is communicated with an intake resonator arranged in front of the vehicle or the like via a throttle body (not shown).

The collector 4 is formed in a substantially box shape along the longitudinal direction of the engine 1, and as shown in FIG. 2, the intake passage 3 for each cylinder opens in the internal space 5 of the collector 4. Positions in which the opening 3a and the opening 6a in which the connection passage 6 for connecting to the supercharger 10 via the duct 8 opens are opened in the inner wall surfaces 5a, 5b facing each other, and are vertically displaced from each other. It is located in. The volume of the internal space 5 of the collector 4, the distance between the inner wall surfaces 5a and 5b, the area, etc.
The optimum shape is set in advance in consideration of the number of cylinders of the engine 1, the displacement, the characteristics of the supercharger 10, and the like.

More specifically, the intake passage 3 for each cylinder extending from the cylinder head mounting flange portion 7 of the intake manifold 2 includes an engine 1 in an internal space 5 of a collector 4.
The opening 6a of the connection passage 6 to the supercharger 10 is opened above the inner wall surface 5b facing the opening 3a. The connecting passage 6 extends from the upper portion of the collector 4 with a slight inclination, and is connected to the discharge port of the supercharger 10 via a duct 8. Incidentally, in FIG. 2, reference numeral 7a designates the intake manifold 2 for injecting fuel into the intake port of each cylinder.
Is a mounting portion for an injector (not shown) provided near the cylinder head mounting surface.

In the intake system of the engine 1 described above, the air discharged from the supercharger 10 is introduced into the collector 4 from the connection passage 6 of the intake manifold 2 via the duct 8. Then, in the internal space 5 of the collector 4, FIG.
As indicated by the arrow, the discharge air from the supercharger 10 collides with the upper portion of the inner wall surface 5a facing the opening 6a of the connection passage 6 and is reflected, and further reflected on the inner wall surface 5b opposite to the inner wall surface 5a. It is collided and reflected, and is supplied to the engine 1 from the opening 3a of the intake passage 3 for each cylinder opened at the bottom of the inner wall surface 5a.

That is, the discharge air pressure-fed from the supercharger 10 into the collector 4 of the intake manifold 2 collides and reflects on the inner wall surfaces 5a and 5b in the collector 4, and the collector 4
The air that has been supercharged by the supercharger 10 is once reflected / compressed in the collector 4 because the air is supplied to the engine 1 by advancing from the inlet side to the outlet side in a substantially "reverse S" shape. Can be distributed evenly to each cylinder of the engine 1 as an air mass having a uniform pressure in which the pulsation energy is attenuated. Moreover, since the connection passage 6 for guiding the discharge air from the supercharger 10 into the collector 4 is arranged so as to face the inner wall surface 5a and introduce the air obliquely from below, it is introduced into the internal space 5. The air does not directly enter the opening 3a of the intake passage 3, but is reliably reflected by the upper portion of the inner wall surface 5a toward the inner wall surface 5b on the opposite side, and is reflected again by the inner wall surface 5b to open the opening portion of the intake passage 3. Flows into 3a.

As a result, even if the supercharger 10 is arranged immediately upstream of the collector 4 due to the restriction of the arrangement space of the engine 1 and the intake system, a simple structure is achieved without using a special passage or control valve. Thus, the intake pulsation from the supercharger 10 can be attenuated. As a result, it is possible to supply air according to the valve opening / closing timing of the engine 1 to improve the intake efficiency, and to increase the knock limit of the engine 1 to improve the output performance and the fuel consumption.

[0019]

As described above, according to the present invention, the air discharged from the supercharger is supplied to the engine in which the supercharger is arranged immediately upstream of the chamber communicating with the intake passage on the cylinder side. Since the opening of the passage leading to the cylinder and the opening of the intake passage on the cylinder side are arranged on the inner wall surfaces facing each other in the chamber and at positions deviated from each other, the discharge air from the supercharger is discharged inside the chamber. The pulsation can be reflected by the wall surface to interfere and attenuate the pulsation, and the pressure can be made uniform and sucked into the cylinder through the intake passage. As a result, intake pulsation generated in the supercharger can be effectively damped without using a special passage or control valve, and engine output performance and fuel consumption can be improved.

[Brief description of drawings]

FIG. 1 is an external view showing an arrangement of an engine and an intake device.

FIG. 2 is a sectional view of the collector.

[Explanation of symbols]

1 engine 3 intake passage 3a opening 4 collector 5a, 5b inner wall surface 6 connecting passages 6a opening 10 supercharger

Claims (2)

[Claims] 1. An intake system for an engine with a supercharger in which a supercharger is arranged immediately upstream of a chamber communicating with an intake passage on the cylinder side, and a passage for introducing discharge air from the supercharger into the chamber. An intake device for a supercharged engine, wherein the intake passage and the intake passage are opened at inner wall surfaces facing each other in the chamber and at positions displaced from each other. 2. The over-payment according to claim 1, wherein a passage for guiding the discharge air from the supercharger into the chamber is arranged so as to face the inner wall surface of the chamber in an oblique direction. Engine intake device.