JP3505491B2 - Silencer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a muffler provided to reduce intake pulsation noise of an automobile.

[0002]

2. Description of the Related Art A muffler called a resonator is often provided in a member forming an intake air circulation portion ( intake passage ) for taking in air into an engine as smoothly as possible. The resonator is provided to reduce the opening and closing of the intake valve of the engine and the pulsating sound (intake sound) generated by the air pressure. As a kind of resonator, there is a side branch 1 as shown in FIGS. (I) FIG. 7 shows a case where the side branch 1 is provided so as to project outward on the outer wall of the inlet 2 which is one of the members forming the intake air circulation portion . (Ii) FIG. 8 shows a case where the side branch 1 is provided along the inner wall of the inlet 2.

[0003]

However, the above (i) ,
The muffler of (ii) has the following problems. (I) In the engine room, since objects other than the inlet 2 are arranged around the inlet 2,
It is necessary to avoid interference with it and the side branch 1. Therefore, the space that can be taken by the side branch 1 is limited, and it is often difficult to improve the sound deadening effect by the side branch 1. (Ii) Since the side branch 1 is provided along the inner wall of the inlet 2, the side branch 1 is provided on the outer wall of the inlet 2 (in the case of (i) )
Although the space that can be taken by the side branch 1 is larger than that of the above, the larger the side branch 1, the smaller the cross-sectional area of the intake circulation portion in the inlet 2 and the smaller the opening area of the inlet 2. As a result, the intake pressure loss increases excessively. An object of the present invention is to provide a silencer that can provide a silencing effect without reducing the opening area of the inlet even when provided in the intake air circulation portion .

[0004]

[Means for solving the problem] (1) Pass through the narrowest part
The intake air circulation portion that opens to the air cleaner through the irregular portion
A side branch is provided at the part connected to the air cleaner.
The side branch extends in the axial direction of the intake air circulation portion , and projects into the air cleaner,
A silencer opening toward the inside of the air cleaner . (2) In front of the part where the side branch is provided
The cross-sectional area of the intake air circulation portion is equal to that of the narrowest intake air circulation portion.
The silencer according to (1), which has a cross-sectional area equal to or larger than a cross-sectional area of the intake air circulation portion of the narrowest portion. (3) The silencer according to (1), wherein the side branch is provided around the intake air circulation portion . (4) The silencer according to (1), wherein the intake air circulation portion is provided around the side branch.

In the above-described silencers (1) to (4), since the side branch is provided in the intake air circulation portion , a silencer effect can be obtained without being restricted by any object other than the intake duct around the intake duct. Obtainable. Further, since the muffler is a side branch that extends in the axial direction of the intake air circulation portion downstream of the narrowest portion, the opening area of the inlet is not reduced. Therefore, the amount of increase in intake pressure loss is smaller than that in the conventional case where the side branch is provided along the inner wall of the inlet.

[0006]

1 to 4 show a silencer according to a first embodiment of the present invention, and FIGS. 5 and 6 show a silencer according to a second embodiment of the present invention. First and Second Embodiments of the Present Invention
The configurations and operations of the parts common to the embodiments or similar parts will be described with reference to FIGS. 1, 2, 4, and 6. The muffler of the embodiment of the present invention is a resonator provided in a member that forms an intake circulation portion ( intake passage ) for taking in air into the engine as smoothly as possible, and is particularly the side branch 10. Side branch 10
As shown in FIG. 2, it is provided in the inlet 30 connected to the air cleaner 20. However, side branch 10
When a duct (not shown) that connects the air cleaner 20 and the inlet 30 is provided, may be provided in the duct.

First, the inlet 30 will be described.
The inlet 30 is located upstream of the air cleaner 20, as shown in FIGS. The inlet 30 has an air intake 31, a narrowest portion 32, and a gradually changing portion 33.
The narrowest part 32 is located downstream of the air intake 31.
The narrowest portion 32 has a cross-sectional area S1 smaller than the passage cross-sectional area S0 of the air intake 31. The gradual change part 33 is the narrowest part 3
It is provided downstream of 2. The passage cross-sectional area of the gradually changing portion 33 increases as it goes downstream from the narrowest portion 32. The passage sectional area S2 at the downstream end of the gradually changing portion 33 is smaller than the passage sectional area S0 of the air intake 31 and larger than the passage sectional area S1 of the narrowest portion 32. Downstream end 33a of the gradually changing portion 33
Is connected to the air cleaner 20.

Next, the side branch 10 will be described. The side branch 10 is provided in the gradually changing portion 33 of the inlet 30. Side branch 10 is the intake flow
It extends in the axial direction of the passage portion 40. The downstream end 11 of the side branch 10 may project into the air cleaner 20 (the illustrated example of the present invention shows the case where it projects into the air cleaner 20). Downstream end 1 of side branch 10
1 is open to the downstream. Side branch 10
4, the side branch 10 is provided around the intake flow section 40 as shown in FIG. 4, or the intake branch section 40 is provided around the side branch 10 as shown in FIG. It is provided in. The passage cross-sectional area S3 of the portion where the side branch 10 is provided is equal to or larger than the passage cross-sectional area S1 of the narrowest portion 32.

Next, the operation will be described. In the embodiment of the present invention, the side branch 10 extending in the passage axial direction downstream of the narrowest portion 32 in the intake air circulation portion 40 upstream of the air cleaner 20.
Is provided, there is no restriction on the mounting from an object other than the intake duct around the intake duct. Further, since the side branch 10 is provided in the gradually changing portion 33 and extends in the axial direction of the intake air circulation portion 40, the side branch 10 does not narrow the opening area of the air intake 31 of the inlet 30. . Therefore, the increase amount of the intake pressure loss is smaller than that in the conventional case where the side branch is provided along the inner wall of the inlet (see FIG. 8). Further, since the downstream end of the side branch 10 may protrude into the air cleaner 20, the side branch 10
The degree of freedom in selecting the axial length of the is greater than in the conventional case (FIGS. 7 and 8).

The parts unique to each embodiment of the present invention will be described below. 1st Example of this invention has shown the case where the side branch 10 is provided in the circumference | surroundings of the intake air circulation part 40 over the perimeter, as shown in FIGS. The upstream end 12 of the side branch 10 has a funnel shape in order to reduce the increase amount of intake pressure loss. The case where the side branch 10 is not provided, the case where the side branch is provided on the outer wall of the inlet, the case where the side branch is provided along the inner wall of the inlet, and the side of the first embodiment of the present invention The intake pressure loss when the branch 10 is provided is as shown in Table 1.

[0011]

[Table 1]

Table 1 will be described in detail below. When the intake pressure loss when the side branch 10 is not provided is 100, the intake pressure loss when the side branch is provided on the outer wall of the inlet (see FIG. 7) is 101, and the side branch is the inlet pressure loss. The intake pressure loss when it is provided along the inner wall (see FIG. 8) is 130, and the intake pressure loss when the side branch 10 of the first embodiment of the present invention is provided is 1.
It is 10. From Table 1, when the side branch 10 of the first embodiment of the present invention is provided, the intake pressure loss is smaller than when it is provided on the inner wall of the inlet (FIG. 7).

The second embodiment of the present invention shows a case where the intake air circulation portion 40 is provided around the side branch 10 as shown in FIGS. Side branch 10
The outer wall 13 is provided with a rib 13a extending from the outer wall 13 in a direction orthogonal to the axial direction of the passage. The side branch 10 is attached to the gradually changing portion 33 via the rib 13a. The upstream end 12 of the side branch 10 has a funnel shape in order to reduce the increase amount of intake pressure loss.

[0014]

EFFECT OF THE INVENTION Claim 1 or Claim 2 or Claim 3
Alternatively, according to the silencer of the fourth aspect, since the side branch is provided in the intake air circulation portion , it is possible to obtain a noise reduction effect without being restricted by an object other than the intake duct around the intake duct. . Further, since the muffler is a side branch that extends in the passage axial direction downstream of the narrowest part, the opening area of the inlet is not reduced. Therefore, the amount of increase in intake pressure loss is smaller than that in the conventional case where the side branch is provided along the inner wall of the inlet.

[Brief description of drawings]

FIG. 1 is a perspective view showing an intake duct provided with a silencer according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the muffler of the first embodiment of the present invention and its vicinity.

FIG. 3 is a conceptual diagram showing a muffling effect of the muffler of the first embodiment of the present invention.

FIG. 4 is a cross-sectional view of the muffler of the first embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a silencer and its vicinity according to a second embodiment of the present invention.

FIG. 6 is a sectional view of a silencer according to a second embodiment of the present invention.

FIG. 7 is a plan view showing a case where a conventional silencer is provided on an outer wall of an inlet.

FIG. 8 is a plan view showing a case where a conventional silencer is provided on an inner wall of an inlet.

[Explanation of symbols]

10 Side Branch 20 Air Cleaner 30 Inlet 31 Air Inlet 32 Narrowest Part 33 Gradual Change Part 40 Intake Distribution ( Intake Passage ) S0 Air Inlet Passage Cross Section S1 Narrowest Passage Cross Section S2 Gradual Change Section Cross-sectional area of passage at downstream end S3 Cross-sectional area of passage where side branch is provided

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Claims (4)

(57) [Claims] 1. An air cleaner that passes through the narrowest portion and the gradually changing portion.
Connected to the air cleaner in the intake air flow section that opens to the
A side branch is provided in the portion, and the side branch extends in the axial direction of the intake air circulation portion , projects into the air cleaner, and extends downstream.
A silencer opening in the air cleaner . Sectional area of wherein the intake flow portion of the site where the side branch is provided, the intake of the narrowest portion
The intake air flow having the same cross-sectional area as the flow passage or the narrowest portion
The silencer according to claim 1, wherein the silencer is larger than the cross-sectional area of the through portion . 3. The silencer according to claim 1, wherein the side branch is provided around the intake air circulation portion . 4. The silencer according to claim 1, wherein the intake air circulation portion is provided around the side branch.