JPH10274117A - Structure of intake duct for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve workability to take out the resonator chamber core of an intake duct with a resonator chamber, and reduce a cost. SOLUTION: A resonator opening part for taking out a core formed in the side of the outer wall of a resonator chamber 3 is juxtaposed as a resonator chamber opening part 8 integrally with a duct flow passage opening part 7 on the air cleaner C side to facilitate taking out of the core. The resonator chamber opening part 8 is closed with a closing part 10b additionally provided at a flange part at the connection end part 10A of an adjoining duct 10. This constitution eliminates a need for machining of a conventional hole for taking out a core an a cover, improves workability, and reduces a cost. Further, when a resonator chamber having a high draft is provided, the core can be taken out as an original shape is left as it is without collapse and the core can be reused.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake duct structure for an engine, and more particularly to a technique for improving workability and reducing costs in manufacturing an intake duct with a resonator chamber.

[0002]

2. Description of the Related Art An integrally formed intake duct with a resonator chamber is provided with an opening 35 for taking out a core from an outer wall of a resonator chamber 34 and for processing a communication hole 38, as shown in FIG. 35 is known in which bolts are fastened with a cover 36 (see Japanese Utility Model Laid-Open No. 3-83364).

[0003]

However, the above-described intake duct structure with a resonator chamber has the following problems. That is, the opening 35 for removing the core from the resonator chamber after casting has a large area. Accordingly, the size of the cover 36 becomes large, and the cost of materials and processing increases.

An object of the present invention is to solve the above-mentioned conventional problems by facilitating the operation of removing the core of the resonator chamber and reducing the processing cost of the opening and the cost of the cover. And

[0005]

For this reason, the invention according to claim 1 is based on a resonator chamber having a predetermined volume space provided in the middle of an intake duct of an internal combustion engine and separated by a partition wall from an intake duct flow path. In the structure of the intake duct having a resonator chamber communicated with the intake duct flow passage at a communication hole formed in the partition wall, the resonator chamber is opened to a connection end of the intake duct with an adjacent duct. An opening for core removal is provided, and a flange formed at the connection end of the adjacent duct with the intake duct,
A closing portion for closing the opening was additionally provided.

As described above, in an intake duct having a resonator chamber separated from an intake duct flow path and a partition wall in an intake duct from an air cleaner of an internal combustion engine to an intake manifold, a core is provided at a connection end portion with the intake duct. Since the opening for taking out is provided, it is easy to take out the core. In addition, this opening is closed at the time of connection with a closed portion provided in addition to a flange portion formed at the connection end of the adjacent duct to make the resonator chamber a private room. This eliminates the need for a conventional core removal opening and a cover for closing the opening during casting of the resonator chamber.

In the invention according to a second aspect, the resonator chamber is formed to extend substantially linearly in a linear portion of the intake duct. As described above, since the resonator chamber is formed so as to extend substantially linearly in the linear portion of the intake duct, the shape of the resonator chamber is simplified, and the castability and the removal of the core are simplified.

According to a third aspect of the present invention, there is provided a processing hole into which a processing tool for processing the communication hole can be inserted into an outer wall of the intake duct corresponding to the resonator chamber, and the processing hole closed after the processing. Provided. As described above, the processing hole for forming the communication hole is provided in the outer wall of the intake duct corresponding to the resonator chamber. A processing tool crosses the resonator chamber through the processing hole to form a communication hole. Therefore, the processing hole may be a minimum hole into which a processing tool can be inserted. In addition, the processing hole is closed safely and securely with a screw plug or the like.

According to a fourth aspect of the present invention, the inner wall of the resonator chamber is provided with a draft so that the cross-sectional area of the resonator chamber increases from the inside toward the opening.
As described above, the cross-sectional area of the resonator chamber increases from the inside toward the opening, and a draft is provided on the inner wall of the resonator so that it is opened. Can be removed from the opening.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 are views showing an embodiment of an intake duct structure having a resonator chamber of the present invention. Figure 1,
In 2, an intake duct having a resonator chamber (hereinafter, referred to as an intake duct)
1) an intake duct flow path 2 for guiding air from an air cleaner C to an intake manifold M via an adjacent duct 10; and a resonator chamber provided in the intake duct flow path 2 and separated by a partition wall 6. And 3. The intake manifold M side of the intake duct flow path 2 is formed in a cylindrical shape so as to be connected by an elastic tube, and the other end of the connection end 1 A on the intake air cleaner C side is connected to the adjacent duct 10. Is formed so as to be connected to the introduction flow passage 10c by the connection flange 9.

The resonator chamber 3 is formed as an independent individual chamber, and communicates with the intake duct flow passage 2 through a communication hole 4 provided in a partition wall 6. The air cleaner C side of the resonator chamber 3 is opened at a resonator chamber opening 8 serving as an opening for removing a core during casting, and a flange 8a provided around the resonator chamber opening 8 is connected to the duct flow path opening. 7 and are integrally formed as a part of the connection flange 9.

FIGS. 1 and 3 show an example in which the resonator chambers 3 and 13 extend substantially linearly into the linear portions of the duct bodies 1 and 11 and are formed in a simple shape. 3 and 4 show an example in which a processing hole 15 is provided in the duct outer wall 11a of the duct main body 11 corresponding to the resonator chamber 13. The processing hole 15 is a hole into which a processing tool for processing the communication hole 14 that connects the partition 16 that separates the resonator chamber 13 and the intake duct flow path 12 can be inserted. After the inner hole is cut and the communication hole 14 is machined, the machined hole 15 is closed with a screw plug (not shown) to seal the hole. When the processing hole 15 is closed with a blind flat plug or the like, a stepped straight hole may be used.

The adjacent duct 10 has an introduction passage 1 for guiding air from an air cleaner (not shown) to the duct body 11.
0c and a flange portion 10a provided at a connection portion 10A for connecting the duct main body 11 and the adjacent duct 10. The flange portion 10a is connected to the connection flange 19 of the flow path opening 17 and closes the closing portion 10b for closing the resonator chamber opening 18.
Are formed.

FIG. 5 shows that the duct body 21 is connected to the resonator chamber 2.
This is an embodiment in which the opening 28 of the resonator chamber of No. 3 is expanded to make it easier to remove the core after casting. The inside of the resonator chamber 23 including the partition wall 26 is formed to have draft angles S1, S2 and the like. Communication hole 24, processing hole 25, opening 27
This is the same as the duct main body 11 of the previous embodiment. FIG.
FIG. 3 shows an engine assembly top view in which the duct main body 1 and the adjacent duct 10 of the embodiment are assembled to an engine E. The other reference numerals in the figure are the same as those in FIG.

Next, the operation will be described. In FIG. 1, at the time of casting, an intake duct flow path 2 requiring a core (not shown) is opened by communicating with a duct flow path opening 7 from the intake manifold M side, and the core is taken out in the same manner as a conventional product. is there. The core (not shown) of the resonator chamber 3 is pulled up from the resonator chamber opening 8 or broken and taken out. In this case, it is easy to take out the core from the resonator chamber 3 because the entire core can be visually checked when viewed from the resonator chamber opening 8 in the direction of the arrow AA. Further, in the example in which the resonator chamber is formed to extend substantially linearly in the intake duct, that is, the duct main body 1, castability and removal of the core are even easier.

Next, the processing of the communication hole 4 is performed by inserting a processing tool from the opening 8 of the resonator chamber. In the example in which the communication hole 14 is formed with the processing hole 15 in the duct outer wall 11a, the processing tool can be used linearly through the processing hole 15 and processing is easy. The processing hole 15 is sealed with a screw plug. Next, the resonator chamber opening 8 is integrally formed with the connection flange 9.

The duct body 1 and the adjacent duct 10 obtained above
Are connected with each other by bolts at the connection flange 9 and the flange portion 10a. With this connection, the closed portion 10b closes the resonator chamber opening 8, and the resonator chamber 3 becomes a closed individual room. In another embodiment (FIG. 5), the core of the resonator chamber 23 is not destroyed by a draft such as a gradient S2 provided on the partition wall 26 and a gradient S1 provided on the inner wall of the resonator chamber 23. Take out.

In FIG. 6, when the duct body 1 is installed in the engine E, the flange portion 10 b of the adjacent duct 10 is fastened and fixed to the connection flange 9 of the duct body 1, and closes the resonator chamber opening 8. Thereby, the air from the air cleaner C enters the intake manifold M via the adjacent duct 10 and the intake duct flow path 2, and the resonator chamber 3 becomes a private chamber that communicates with the intake duct flow path 2 only through the communication hole 4. It functions as a resonator.

[0019]

As described above, according to the first aspect of the present invention, the core can be easily taken out from the opening of the resonator chamber provided on the air cleaner side of the resonator chamber. Therefore, the core is not destroyed much, and even if the core is broken, it can be visually observed. Further, a large opening and a cover for taking out the core as in the related art are not required, so that the cost of processing the cover mounting portion and the cover itself can be omitted.

According to the second aspect of the present invention, since the resonator chamber is provided substantially linearly in the linear portion of the intake duct, the shape of the resonator chamber is simplified, casting is easy, and the core can be taken out. It became easier. According to the third aspect of the present invention, since the processing hole for processing the communication hole is provided on the outer wall of the intake duct corresponding to the resonator chamber, the processing tool can be used linearly, the work is easy, and the processing tool can be passed. Can be kept to the minimum required. Further, the processed hole can be closed safely, reliably, and inexpensively with a general screw plug or the like.

According to the fourth aspect of the present invention, since the resonator chamber extends toward the opening, the core can be taken out without breaking. The work is simpler and the core can be reused, resulting in a large cost reduction.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of an intake duct structure with a resonator chamber of the present invention.

FIG. 2 is a view taken in the direction of arrows AA in FIG. 1;

FIG. 3 is a longitudinal sectional view showing an embodiment in which a processing hole is provided in an outer wall of a resonator chamber.

FIG. 4 is a cross-sectional view taken along the line BB of FIG. 3;

FIG. 5 is a longitudinal sectional view showing an embodiment in which a draft is provided on the inner wall of the resonator.

FIG. 6 is a top view of an engine assembly in which the embodiment of the present invention is assembled to an engine.

FIG. 7 is a longitudinal sectional view showing a conventional intake duct with a resonator chamber.

[Explanation of symbols]

 1, 11, 21 Intake duct body with resonator chamber 3, 13, 23 Resonator chamber 4, 14, 24 Communication hole 5, 15, 25 Processing hole 6, 16, 26 Partition wall 7, 17, 27 Duct flow path opening 8, 18, 28 Resonator chamber opening 9 Connection flange 10 Adjacent duct 10a Flange 10b Closed portion 10c Introductory flow path 11a Intake duct outer wall C Air cleaner M Intake manifold

Claims (4)

[Claims] 1. A resonator chamber comprising a predetermined volume space provided in a middle of an intake duct of an internal combustion engine and separated by an intake duct flow path and a partition, wherein said communication chamber has a communication hole formed in said partition. In a structure of an intake duct having a resonator chamber communicated with an intake duct flow path, an opening for taking out a core for opening the resonator chamber is provided at a connection end of the intake duct with an adjacent duct, and the intake of the adjacent duct is performed. A structure of an intake duct in an internal combustion engine, wherein a closing portion for closing the opening is added to a flange portion formed at a connection end portion with the duct. 2. The structure of an intake duct in an internal combustion engine according to claim 1, wherein said resonator chamber is formed to extend substantially linearly in a linear portion of the intake duct. 3. A processing hole into which a processing tool for processing the communication hole can be inserted into an outer wall of an intake duct corresponding to the resonator chamber, wherein the processing hole is closed after the processing. The structure of an intake duct in an internal combustion engine according to claim 1 or 2, wherein: 4. The resonator chamber according to claim 1, wherein a draft is provided on an inner wall of the resonator chamber so that a cross-sectional area of the resonator chamber increases from the inside toward the opening. The structure of an intake duct in the internal combustion engine according to the above description.