JPH09195896A - Intake device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a high-frequency intake sound, by providing an air rectifying member, at the part at the downstream side of an idle speed control valve, of an idle speed control passage. SOLUTION: An idle speed control(ISC) valve 13 controls the air flow rate flowing through the ISC valve 13 by the rotation of a rotary bulb 6, and it can set the idle rotation frequency at a desired rotation frequency. The air passing through the ISC valve 13 generates a turbulance by being throttled, and the turbulance of the flow passes an ISC rear passage 7 and an ISC main passage 9, and oscillates a resin suction system so as to generate a high-frequency strange noise. And an air rectifying member 8 is provided at the part at the downstream side of the ISC valve 13, of an ISC passage 12. As a result, the air disturbed when passing through the ISC valve 13 is rectified when passing through the air rectifying member 8, and the force to oscillate the member at the downstream side is made weaker, so as to reduce the radiated strange sound.

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 internal combustion engine equipped with an idle speed control device,
Particularly, it relates to a structure for reducing high-frequency intake noise generated by an idle speed control device.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Patent Laid-Open No. 172020/1993, an idle speed control device may be provided in an intake system of an internal combustion engine in order to control idle rotation of the internal combustion engine. The idle speed control device has an idle speed control passage bypassing a throttle valve provided in the main intake passage and an idle speed control valve provided in the middle of the idle speed control passage. The idle speed control valve has, for example, a valve housing and a rotary valve rotatably provided therein, and is rotated by rotating the rotary valve to adjust the valve opening determined by the rotary housing and the rotary valve. The idle flow speed is set to an arbitrary speed by controlling the flow rate of air flowing through the speed control passage.

[0003]

However, the conventional device has the following problems. The air flowing through the idle speed control passage is throttled because the flow area of the idle speed control passage is smaller than that of the main passage, and high-frequency turbulence is generated when passing through the idle speed control valve. (Sound) is generated. This abnormal sound is made of an intake manifold made of resin,
This is a particular problem for intake systems with low rigidity. (Although an aluminum intake manifold also generates high-frequency air vibration, it is not at a level where it is a problem as vehicle interior noise due to its high rigidity.) An object of the present invention is to reduce high-frequency intake noise, idle speed. An object is to provide an intake system for an internal combustion engine equipped with a control device.

[0004]

The present invention to achieve the above object is as follows. (1) In an intake device for an internal combustion engine, comprising an idle speed control device having an idle speed control passage and an idle speed control valve provided in the idle speed control passage, the idle speed control passage in the idle speed control passage An intake device for an internal combustion engine, in which an air rectifying member is provided at a portion downstream of the valve. (2) The intake device for an internal combustion engine according to (1), wherein the intake device has an intake manifold downstream of the idle speed control device, and the intake manifold is made of resin.

In the above device (1), air is introduced into a portion of the idle speed control passage downstream of the idle speed control valve (including a portion of the idle speed control passage downstream of the idle speed control valve and the idle speed control valve). Since the rectifying member is provided, the air disturbed when passing through the idle speed control valve is rectified when passing through the air rectifying member, and the force for vibrating the member on the downstream side is weak, and the member on the downstream side is weakened. The abnormal noise radiated from is reduced. In the device of the above (2), even if the intake manifold is made of resin in which high frequency noise is extremely problematic, the high frequency noise is sufficiently small, and the resin intake manifold can be adopted. The abnormal noise reduction effect is great because the idle speed control device side, which is the high frequency abnormal noise generation source, does not perform the abnormal noise reduction measures on the resin side, but the abnormal noise generation measures.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An intake system for an internal combustion engine according to a preferred embodiment of the present invention will be described with reference to FIGS. FIG.
As shown in FIG. 3, an intake system 1 for an internal combustion engine according to an embodiment of the present invention includes a throttle body 2, an intake manifold 10 connected to the downstream side of the throttle body 2, and an idle speed control device connected to the throttle body 2 ( ISC
Device) 11. The throttle body 2 has a throttle body main passage 3. The intake manifold 10 is preferably made of resin. However, the intake manifold 10 may be made of aluminum or a stainless pipe.

The ISC device 11 has an idle speed control passage (ISC passage) 12 which is in parallel with the throttle body main passage 3 and an idle speed control valve (ISC valve) 13 provided in the middle of the ISC passage 12. . The ISC passage 12 branches from an upstream portion of the throttle valve 14 of the throttle body main passage 3 and joins at a downstream portion of the throttle valve 14.
The ISC passage 12 includes an idle speed control valve front passage (upstream of the ISC valve) 4 upstream of the ISC valve 13, an idle speed control valve rear passage (downstream of the ISC valve) 7 downstream of the ISC valve 13, and an ISC. And an idle speed control main passage (ISC main passage) 9 connected downstream of the valve 13 and downstream of the ISC valve rear passage 7. The ISC valve 13 includes an idle speed control valve housing (ISC valve housing) 5,
A valve body (for example, a rotary valve 6) rotatably provided in the ISC valve housing 5.

In the portion of the ISC passage 12 downstream of the ISC valve 13 (including the portion of the ISC passage 12 on the downstream side of the ISC valve 13 and the ISC valve 13 itself), an air rectifying member 8 for rectifying the air passing therethrough. Is provided. The air rectifying member 8 is preferably arranged immediately after the ISC valve 13. However, the air rectifying member 8
May be provided near the inlet to the throttle body main passage 3 and / or the intake manifold 10 as long as it is a portion of the ISC passage 12 after the ISC valve 13.

The air rectifying member 8 may have any structure as long as it has a structure for rectifying the air passing therethrough. For example, the following first to seventh examples can be adopted.
As shown in FIG. 3, the first example is a structure that is separate from the throttle body 2 and has a plurality of straightening vanes spaced from each other and connected to each other. The second example is that in FIG. 3, a plurality of straightening vanes are arranged at intervals and are connected to each other.
Structure that is permanently attached to the throttle body 2.
As shown in FIGS. 4 and 5, the third example is a structure in which the throttle body 2 and the ISC valve 13 are separate bodies and are sandwiched between the throttle body 2 and the ISC valve 13. The fourth example is a structure in which a grid is provided at the outlet of the ISC valve housing 5, as shown in FIG. The fifth example is shown in FIG.
Also, as shown in FIG. 8, a structure in which a lattice is provided on the casing itself surrounding the ISC valve housing 5. The sixth example, as shown in FIGS. 9 and 10, is composed of a gasket of a punching separator and includes a throttle body 2 and an IS.
Separated from the C valve 13, the throttle body 2 and IS
Structure that is sandwiched between C valve 13. In the seventh example, as shown in FIG. 11, the structure is made of wire mesh, is separate from the throttle body 2 and the ISC valve 13, and is sandwiched between the throttle body 2 and the ISC valve 13.

Next, the operation will be described. ISC valve 1
3 rotates the rotary valve 6 to throttle the outlet of the ISC valve housing. By adjusting the throttle amount, the flow rate of the air flowing through the ISC valve 13 can be controlled and the idle speed can be set to an arbitrary speed. The air passing through the ISC valve 13 is
It is squeezed by and causes turbulence in the flow (high-frequency pressure fluctuation).
The turbulence of the flow passes through the ISC valve rear passage 7 and further through the ISC main passage 9 to excite the resin intake system (including the resin intake manifold 10) to generate high-frequency abnormal noise. When the intake system is made of resin, this abnormal noise is high because of its low rigidity. However, even if the intake system is made of aluminum, stainless steel pipe, or the like, the sound pressure level varies depending on the magnitude.

However, in the embodiment of the present invention, the ISC passage 1
The air rectifying member 8 is provided on the downstream side of the ISC valve 13 among the two.
Since the air that has been disturbed when passing through the ISC valve 13 is rectified when passing through the air rectifying member 8, the force for vibrating a member (such as an intake manifold) on the downstream side thereof is weak. The abnormal noise emitted from the member on the downstream side is reduced. Further, since the high frequency abnormal noise is reduced by providing the air rectifying member 8, the high frequency abnormal noise is sufficiently small even if the intake manifold 10 is made of resin. As a result, it becomes possible to adopt a resin intake manifold. The abnormal noise reduction effect is large and effective because the resin side does not take various noise reduction measures but the ISC device side, which is the high-frequency noise generation source, takes abnormal noise suppression measures.

[0012]

According to the apparatus of the first aspect, since the air rectifying member is provided in the portion of the ISC passage downstream of the ISC valve, the air disturbed when passing through the ISC valve passes through the air rectifying member. Sometimes, the force that is rectified and vibrates the member on the downstream side is weak, and the abnormal noise emitted from the member on the downstream side becomes small. According to the apparatus of the second aspect, the high-frequency noise is sufficiently small, regardless of whether the intake manifold is made of resin, and thus the resin intake manifold can be used. The abnormal noise reduction effect is large because the resin side does not take various noise reduction measures but the ISC device side that is the high-frequency noise generation source takes abnormal noise suppression measures.

[Brief description of the drawings]

1 is a schematic diagram of an intake system for an internal combustion engine according to an embodiment of the present invention,
It is a sectional view of a portion of an SC device and a throttle body.

2 is a cross-sectional view of the device portion of FIG. 1 in a direction orthogonal to FIG.

3 is a perspective perspective view of the device portion of FIG. 1. FIG.

FIG. 4 is a perspective view of an air rectifying member of a third example applicable to the apparatus of FIG. 1 and its vicinity.

5 is a plan view of the air rectifying member of FIG.

FIG. 6 is a perspective view of an air rectifying member of a fourth example applicable to the apparatus of FIG. 1 and its vicinity.

FIG. 7 is a perspective view of an air rectifying member of the fifth example applicable to the apparatus of FIG. 1 and its vicinity.

FIG. 8 is a plan view of the air rectifying member of FIG.

FIG. 9 is a perspective view of an air rectifying member of a sixth example applicable to the apparatus of FIG. 1 and its vicinity.

FIG. 10 is a plan view of the air rectifying member of FIG.

FIG. 11 is a plan view of an air rectifying member of a seventh example applicable to the device of FIG.

[Explanation of symbols]

1 Internal Combustion Engine Intake Device 2 Throttle Body 3 Throttle Body Main Passage 3 4 Idle Speed Control Valve Front Passage (IS
C valve front passage) 5 idle speed control valve housing (ISC valve housing) 6 valve body (for example, rotary valve) 7 idle speed control valve rear passage (IS
C valve rear passage) 8 Air rectifying member 9 Idle speed control main passage (ISC
Main passage) 10 Intake manifold 11 Idle speed control device (ISC device) 12 Idle speed control passage (ISC passage) 13 Idle speed control valve (ISC valve) 14 Throttle valve

Claims (2)

[Claims] 1. An intake system for an internal combustion engine comprising an idle speed control device having an idle speed control passage and an idle speed control valve provided in the idle speed control passage. An intake device for an internal combustion engine, comprising an air rectifying member provided downstream of a speed control valve. 2. The intake device for an internal combustion engine according to claim 1, wherein the intake device has an intake manifold downstream of the idle speed control device, and the intake manifold is made of resin.