JP2001207925A - Air duct and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air duct constituted by integrally having a resonator provided side by side on a duct part capable of reducing manufacturing cost and its manufacturing method. SOLUTION: This air duct integrally has a duct part and a resonator part 59 juxtaposed on the duct part and is made of a first part 61 including the resonator part and a second part 63 except for the first part, the first part is made of a bulkhead part 63 to partition the duct part and the resonator part and a first main body part 67, and the first main body part and the second part are connected to each other so that the bulkhead part is sandwiched between the first main body part and the second part. This manufacturing method is constituted by including a molding step to separately mold the second part except for the first part including the resonator part, the bulkhead part and the first main body part except for bulkhead part out of the first part, a bulkhead part arranging step and a connecting step so that the bulkhead part is sandwiched between the first main body part and the second part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air duct used for an intake system pipe of an internal combustion engine and a method of manufacturing the same, and more particularly, to an air duct integrated with a resonator provided alongside the duct. And a method of manufacturing the air duct.

[0002]

2. Description of the Related Art Attempts have been made to reduce noise generated from an internal combustion engine itself or a device attached thereto, which has been frequently used as a power source. For example, automobiles and motorcycles equipped with an internal combustion engine (hereinafter referred to as "automobiles and the like").
In the case, since the noise can be heard by a passenger such as an automobile or a person around the automobile, etc., the comfort of the passenger may be impaired or the surrounding people may be uncomfortable. Various methods of reducing have been used.
Among such noises, in order to reduce so-called intake noise in which the opening and closing of an intake valve of an internal combustion engine is a sound source, a resonator portion is provided alongside a duct portion through which gas flows in an air duct ( For example, JP-A-8-86256
No.). The resonator section has an air pocket space structure communicating with the duct section (the same publication, FIGS. 1 to 4),
The opening and closing of the intake valve of the internal combustion engine reduces the intake sound as a sound source by the action of reflection, absorption, cancellation, and the like.

FIG. 9 is a perspective explanatory view (FIG. 1 of the same publication) for explaining an embodiment of Japanese Patent Laid-Open Publication No. 8-86256. With reference to FIG. 9, a description will be given of a conventional air duct in which a resonator unit is provided in a duct unit. First, a part A of the air duct, a part B integrating the rest of the air duct and a part of the resonator, and a part C of the remaining part of the resonator
Are molded with resin. And these three
Conventional air ducts have been manufactured by joining the end faces of members A, B, and C, respectively. In the conventional air duct 10 shown in FIG. 9, a duct portion 31 is formed between an inlet 26 and an outlet 28, and the duct portion 31 is
(The interior of the resonator unit 12 forms an air reservoir space 30). The duct part 31 and the resonator part 12 (the air reservoir space 30) communicate with each other through the communication pipe 18.

[0004]

However, a conventional air duct in which a resonator is provided in addition to a duct as shown in FIG. 9 is composed of three members A, B, and C. Must be joined at two locations. That is, two joint portions, a first joint portion joining the member A and the member B and a second joint portion joining the member B and the member C, are required. The bonding between the members is performed by welding such as vibration welding, hot plate welding, headband injection welding, or by bonding with an adhesive, but in any case, the number of man-hours increases, equipment preparation, production capacity decreases. And the like, and as a result, there is a problem of increasing the manufacturing cost of the air duct.

Accordingly, in the present invention, the manufacturing cost of the air duct can be reduced by reducing the number of joints required when manufacturing an air duct integrally having a resonator provided in parallel with the duct. An object of the present invention is to provide a duct and a method for manufacturing the duct.

[0006]

The air duct of the present invention (hereinafter referred to as "the main air duct") is an air duct having a duct unit and a resonator unit provided in parallel with the duct unit. A duct including a first portion including the resonator portion, and a second portion other than the first portion, wherein the first portion is a partition portion that separates the duct portion and the resonator portion; The first body portion and the second portion so that the partition portion is sandwiched between the first body portion and the second portion. Are joined together to form an air duct. In this way, the present air duct is composed of three members, a partition part, a first main body part, and a second part, and the partition part is arranged at a predetermined position of the first main body part, When the parts are joined, the partition part is sandwiched and fixed between the first body part and the second part. For this reason, the main air duct can be formed from the three members of the partition wall portion, the first main body portion, and the second portion only by one joint (joining of the first main body portion and the second portion). Ducts can reduce the number of joints required to manufacture them and reduce manufacturing costs.

[0007] The resonator section has a communicating pipe (sometimes called a tuning pipe) projecting from the duct section into the resonator section and communicating the duct section and the resonator section.
Are often provided. Depending on the specification (thickness, length, etc.) of the communication pipe, the noise reduction effect changes (for example, the frequency of the reduced noise changes), so that a desired noise reduction effect can be obtained. A communication pipe is provided.
It is easiest to form such a communication tube in the partition wall portion among the three members. For example, the formation of the first main body portion involves problems such as an extremely complicated mold.

The first body portion and the second portion can be joined by any method as long as they are fixed to each other. For example, the first body portion and the second portion can be joined by rivets or bolts, or by an adhesive. It may be adhered. However, from the viewpoint of securely joining the two and using no dissimilar parts, the joining of the first main body portion and the second portion is performed by any of vibration welding, hot plate welding, and headband injection welding. Is preferred. In addition, vibration welding is to perform thermal welding by vibrating under pressure, and hot plate welding is to perform hot welding by pressing a hot plate, and headband-shaped injection welding is to put a welding material around a bonding surface with a headband. It is emitted in a shape, and is sometimes abbreviated as "DSI". In addition, the head-shaped injection welding (DSI) is an injection molding method developed by Japan Steel Works, Ltd. After molding different semi-finished products in the same mold apparatus, the required mold is moved. A method of joining the semi-finished products and injecting the resin into a headband shape around the joining surface and joining (DIE SLIDE)
INJECTION). In this DSI, the three members of the second part, the partition part, and the first main body part are molded in the same mold apparatus, but the three members are formed in the mold apparatus.
Each member is molded as a separate one.

The method for manufacturing an air duct of the present invention (hereinafter, referred to as
This is called "this method." ) Is a method of manufacturing an air duct integrally including a duct portion and a resonator portion provided in parallel with the duct portion, wherein the second portion other than the first portion including the resonator portion, and the first portion A molding step of separately molding a partition portion separating the duct portion and the resonator portion, and a first main body portion excluding the partition portion of the first portion; and a predetermined position of the first main body portion. Arranging the partition portion and assembling the first portion with the first main portion and the second main portion so that the partition portion is sandwiched between the first main portion and the second portion. And a joining step of joining the parts to each other.
In this way, the second portion, the partition wall portion, and the first main body portion are separately molded in the molding step, and the first partition portion is arranged at a predetermined position of the first main body portion in the partition wall portion arrangement step, and the first portion is assembled. Then, in the joining step, the first body portion and the second portion of the first portion assembled in the partition portion arranging step are joined in a predetermined positional relationship, and the joining causes the partition portion to move between the first body portion and the second portion. And the air duct can be manufactured and fixed. By joining the first body portion and the second portion in the joining step, the partition wall portion is sandwiched and fixed between the first body portion and the second portion. This method is necessary when manufacturing the present air duct, since the present air duct can be formed only from the three members of the partition wall portion, the first main body portion, and the second portion only by joining with the second portion). The number of joints can be reduced, and the production cost of the air duct can be reduced.

As described above, in the case where a communication pipe is provided in the manufactured air duct, which protrudes from the duct section into the resonator section and communicates the duct section and the resonator section, the communication pipe is preferably formed in the partition wall portion. . For this purpose, in the molding step, a communication pipe may be formed in the partition wall.

[0011] The joining of the first body portion and the second portion in the joining step may be performed by any method as long as they are fixed to each other as described above. They may be joined by bolts or adhered by an adhesive. However, from the fact that the two are securely joined and the dissimilar parts are not used, the joining between the first body portion and the second portion is
It is preferable that the welding be performed by any of vibration welding, hot plate welding, and headband injection welding. The terms of vibration welding, hot plate welding, and headband injection welding are as described above. In the case of headband injection welding (DSI),
3 of the second part, the partition part, and the first body part
The members are molded in the same mold apparatus, but in the mold apparatus, each of the three members is molded as a separate one,
In the molding step of the present method, "the second part, the partition wall part, and the first main body part are separately molded".

[0012]

Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited by these.

FIG. 1 shows an air duct 51 according to an embodiment.
FIG. 2 is a perspective view (partially cut away) of the air duct 51 shown in FIG. 1 as viewed from the substantially opposite side of FIG. 1 (the direction of arrow A in FIG. 1). FIG. 3 is a partially enlarged view of FIG. And
FIG. 4 is a perspective view (a viewing direction and a position are the same as in FIG. 1) in which a later-described second part 63 is removed from the air duct 51. FIG. 5 is a perspective view of the first part 61 to the partition part 65 shown in FIG. FIG. 2 is a perspective view (a viewing direction and a position are the same as those in FIG. 1) from which FIG. Further, FIG. 6 is a perspective view showing a view from substantially the opposite side of FIG. 5 (the direction of arrow B in FIG. 5), and FIG. 7 is a perspective view showing a view of FIG. 6 obliquely from below. The air duct 51, which is the present air duct, will be described with reference to FIGS. The air duct 51 is
It is attached to the front end (the end farthest from the engine) of the intake system of the engine (internal combustion engine) of a passenger car (not shown).

First, with reference to FIG. 1 to FIG. 3, mainly the external structure of the air duct 51 will be described. The air duct 51 has, at one end thereof, an air inlet 5 open to the atmosphere.
3 and an exhaust port 55 connected to an engine (not shown) on the other end side. The combustion air is taken in from the intake port 53 and exhausted from the exhaust port 55 to the engine (not shown). And supply. The air duct 51 includes a duct portion 57,
And a resonator unit 59 provided alongside the duct unit 57. The air duct 51 includes a first portion 61 including the resonator 59 and a second portion 63 other than the first portion 61.

Next, the internal structure of the air duct 51 will be mainly described with reference to FIGS. The first part 61 includes a partition wall part 65 and a first main body part 67. The partition wall portion 65 includes a communication pipe 68 and the other partition wall main body 64. The partition main body 64 fits into a predetermined position of the first main body 67 and separates the duct 57 from the resonator 59, whereby an air pocket space 71 of the resonator 59 is formed. I have. The communication pipe 68 protrudes from the duct 57 to the inside of the resonator 59 and connects the duct 57 (within) and the resonator 59 (within). Then, the first body portion 67 and the second portion 63 are joined to form the partition wall portion 6.
The upper edge portions 66a and 66b, which are a part of 5, are sandwiched between the first body portion 67 and the second portion 63, and the partition wall portion 65 is fixed (particularly, see FIG. 3).

Although the joining of the first body portion 67 and the second portion 63 is performed by headband injection welding here, other methods such as vibration welding, hot plate welding, rivets, and bolts are used. Alternatively, it may be performed by bonding with an adhesive or the like.

FIG. 8 is a perspective view of the air duct of another embodiment in which the second portion 63 and the partition wall portion 65 are removed (the viewing direction and position are the same as in FIG. 6). Compared to the air duct 51 shown in FIGS. 1 to 7, the air duct shown in FIG. 8 is different from the air duct 51 shown in FIG.
The tongue 70a is formed in some places along the
a is formed at the joint between the first main body portion 67 and the second portion 63, except that
Other points are the same. The partition wall 65 is formed in the recess 70b.
By fitting the tongue portion 70a of the first body portion 67, the partition wall portion 65 can be easily and accurately arranged at a predetermined position of the first main body portion 67, and the partition wall portion arranged at a predetermined position of the first main body portion 67 can be easily inserted. 65 can be prevented from being accidentally displaced from the first main body portion 67 along the upper edges 66a, 66b.

Next, the present method (method of manufacturing the air duct 51) will be described. First, as a molding step,
The second portion 63, the partition wall portion 65, and the first main body portion 67 as shown in FIGS. 5 to 7 are separately molded. Here, the third part 63, the partition part 65, and the first body part 67
Although all the members were formed by the injection molding method, it is not limited to this, and it goes without saying that another molding method (for example, a blow molding method) may be used. In addition,
As the resin material forming the three members, the same material as that used for forming the conventional air duct can be used. Then, in the molding step, the communication pipe 68 is formed in the partition wall portion 65.

Secondly, as a partition part arranging step, as shown in FIG. 4, the partition part 65 is arranged at a predetermined position of the first main body part 67 and the first part 61 is assembled. In order to easily arrange the partition wall portion 65 at a predetermined position of the first main body portion 67 in the partition wall portion arranging step, as shown in FIG.
a, a tongue 70a is formed in some places along the 66b, and a recess 70b into which the tongue 70a can be fitted is formed in a joint portion between the first body portion 67 and the second portion 63, and the recess 70b is formed in the recess 70b. The tongue portion 70a of the partition wall portion 65 may be fitted.

Third, as a joining step, the first body portion 67 and the second portion 63 of the first portion 61 assembled in the partition wall portion arranging step are joined in a predetermined relationship.
In this joining step, both upper edges 66a and 66b, which are part of the partition wall portion 65, are sandwiched between the first main body portion 67 and the second portion 63, and the partition wall portion 65 is fixed (particularly, FIG. reference). The joining of the first body portion 67 and the second portion 63 in the joining step at this time is performed by headband injection welding as described above, but other methods such as vibration welding and hot plate welding are used. , Rivets, bolts, adhesives or the like.

Here, since the joining of the first body portion 67 and the second portion 63 is performed by headband injection welding, the above-described molding step, partition wall portion arranging step, and joining step are actually the same. This is performed in the mold apparatus.

As described above, according to the present air duct and the present method, the partition wall portion, the first main body portion, and the second portion are formed by only one joint (joining of the first main body portion and the second portion).
Since this air duct can be formed from the members,
Compared to the case where two joints are conventionally performed, the number of joints required for manufacturing can be reduced, and the manufacturing cost of the air duct can be reduced. In addition, the number of joints that are usually weak physically, chemically, and thermally can be reduced, so that the reliability of the air duct can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an air duct of one embodiment.

FIG. 2 is a perspective view (partly cut away) of the air duct shown in FIG. 1 as viewed from the opposite side.

FIG. 3 is a partially enlarged view of FIG. 2;

FIG. 4 is a perspective view in which a second portion is removed from an air duct.

FIG. 5 is a perspective view of the first part shown in FIG. 4 with a partition part removed.

FIG. 6 is a perspective view showing the air duct shown in FIG. 5 as viewed from the opposite side.

FIG. 7 is a perspective view showing the air duct shown in FIG. 6 as viewed obliquely from below.

FIG. 8 is a perspective view in which a second portion and a partition portion are removed from the air duct of another embodiment.

FIG. 9 is a perspective view showing a conventional air duct in which a resonator unit is provided in a duct unit.

[Explanation of symbols]

 51 Main air duct 53 Intake port 55 Exhaust port 57 Duct part 59 Resonator part 61 First part 63 Second part 64 Partition body part 65 Partition parts 66a, 66b Upper edge part 67 First body part 68 Communication pipe 70a Tongue part 70b Recess 71 Air pocket space

Claims (6)

[Claims] 1. An air duct integrally comprising a duct portion and a resonator portion provided adjacent to the duct portion, wherein a first portion including the resonator portion and a second portion other than the first portion are provided. Wherein the first portion comprises: a partition portion that separates the duct portion and the resonator portion; and a first main body portion excluding the partition portion of the first portion. An air duct, wherein the first body portion and the second portion are joined so as to be sandwiched between one body portion and the second portion. 2. The air duct according to claim 1, wherein a communication pipe projecting from the duct section into the resonator section and communicating the duct section with the resonator section is formed in the partition wall portion. 3. The air duct according to claim 1, wherein the joining of the first main body portion and the second portion is performed by any of vibration welding, hot plate welding, and headband injection welding. 4. A method of manufacturing an air duct integrally comprising a duct portion and a resonator portion provided in parallel with the duct portion, wherein a second portion other than the first portion including the resonator portion, A molding step of separately molding a partition portion of the first portion separating the duct portion and the resonator portion, and a first main body portion excluding the partition portion portion of the first portion; Arranging the partition part at a predetermined position and assembling the first part; and partitioning the first body part so that the partition part is sandwiched between the first body part and the second part. A joining step of joining the second part. 5. In the manufactured air duct, a communication pipe projecting from the duct portion to the inside of the resonator portion and communicating the duct portion and the resonator portion is formed in the partition portion in the molding step. The manufacturing method according to claim 4, wherein 6. The method according to claim 4, wherein said joining step is performed by any of vibration welding, hot plate welding, and headband injection welding.