JP2002070673A - Vehicular intake manifold and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the degradation of jointing strength in the vicinity of engine mounting flanges in a vehicular intake manifold provided with plural branch pipes horizontally arranged side by side whose projection chart to a vertical plane has a shape bent nearly at 90 deg. and whose one-side ends are commonly connected to a surge tank, and the engine mounting flanges commonly continuously mounted to the other-side ends of the respective branch pipes, and particularly in a vehicular intake manifold composed by welding a pair of jointing members formed of a synthetic resin to each other. SOLUTION: A welding margin in the direction perpendicular to the pressing direction 39 of a part corresponding to a slanting part 32a out of welding margins set before welding in at least one of first and second jointing members 15 and 16 along a jointing line 32 is set larger than that in the direction perpendicular to the pressing direction 39 of the remaining parts other than the slanting part 32a of the jointing line 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plurality of branches which have a shape projected on a vertical plane bent at substantially 90 degrees, one end of which is commonly connected to a surge tank, and which are arranged in parallel in the horizontal direction. TECHNICAL FIELD The present invention relates to a vehicle intake manifold having a pipe and an engine mounting flange commonly connected to the other end of each branch pipe, and particularly to a vehicle constituted by welding a pair of joining members made of synthetic resin to each other. The present invention relates to an improvement in a welded joint structure in an intake manifold and a method of manufacturing a vehicle intake manifold having the improved welded joint structure.

[0002]

2. Description of the Related Art Conventionally, such a vehicle intake manifold is already known, for example, from WO97 / 15755.

[0003]

Incidentally, the joint portion of the vehicle intake manifold, which is formed by welding a plurality of joining members made of synthetic resin, needs to have sufficient joining strength to withstand the internal pressure. In addition, it is necessary to maintain sufficient joint strength and rigidity in the vicinity of the engine mounting flange in the joint portion in view of the fact that the fuel rail and the like are arranged near the flange.

[0004] On the other hand, when welding a joining member made of a synthetic resin, it has been widely practiced to set the welding allowance substantially uniformly over the entire area of the joining line.
For example, EP-0 discloses that a joining line having not only a plane perpendicular to the pressing direction at the time of welding but also an inclined portion or a curved surface portion can shorten the welding time and improve the efficiency.
568560B1 and JP-A-5-177712
It is already known in Japanese Patent Publication No.

Therefore, a plurality of branch pipes having a shape projected on a vertical plane bent at substantially 90 degrees and having one end commonly connected to the surge tank and arranged in parallel in the horizontal direction, A first joining member made of synthetic resin, which comprises a vehicle intake manifold having an engine mounting flange commonly connected to the other end of the vehicle, and an engine mounting flange integrated with each other to form a part of each branch pipe. And a second joining member made of synthetic resin, which constitutes the remaining portion of each branch pipe, is joined in a loop shape with an inclined portion disposed substantially half way around each branch pipe near the engine mounting flange. When they were manufactured so as to be welded to each other on the line, the joining strength of the inclined portion in the joining line was lower than that of other portions, and the necessary joining strength could not be obtained.

This is considered to be due to the fact that the inclined portion of the joining line cannot receive effective reinforcing backup during welding. That is, since the inclined portion is arranged on substantially half the circumference of the branch pipe while being inclined with respect to the pressurizing direction when the two joining members are pressurized with each other during welding, the inclined portion constitutes the entire inner circumference of the intake passage. In this way, the cylindrical portion previously provided in the first joining member and a part of the inclined portion are arranged so as to overlap in the pressing direction during welding, and the first and second joining members are mutually applied. This is because, when pressing, it is difficult to receive a portion corresponding to the inclined portion on the first joining member side with a mold.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made in view of the above circumstances.
It is another object of the present invention to provide a manufacturing method for manufacturing the intake manifold.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, the projection on a vertical plane is approximately 9%.
A plurality of branch pipes having a shape bent at 0 degrees and having one end commonly connected to the surge tank and arranged in parallel in the horizontal direction, and an engine mounting commonly connected to the other end of each branch pipe A first joining member made of synthetic resin, which comprises a flange, and a part of each branch pipe integrally provided with an engine mounting flange, and a second joining member made of synthetic resin, which constitutes the rest of each branch pipe. A member is joined in a loop shape with an inclined portion which is inclined with respect to a pressing direction when both joining members are mutually pressurized at the time of welding and which is arranged on a substantially half circumference on the other end side of each branch pipe. In a vehicle intake manifold welded to each other by a line, at least one of the first and second joining members along the joining line has a portion corresponding to the inclined portion in a welding margin set before welding. Melting in a direction perpendicular to the pressing direction Die, characterized in that it is set larger than in the direction of the welding margin orthogonal to the pressing direction of the site of the remaining other than the inclined portion of the junction line.

According to the structure of the first aspect of the present invention, when the first and second joining members are mutually pressed and welded, the first joining member of the first and second joining members is used. Even if the inclined portion is bent due to the lack of a reinforcement backup of the inclined portion at the portion overlapping the cylinder portion provided along the pressing direction with the member provided, the direction perpendicular to the pressing direction with other portions The welded portion is welded more by an amount corresponding to the difference in the welding allowance along the joint line, and the joining strength is made substantially uniform over the entire circumference of the joining line, or the joining strength of the inclined portion is made larger than other portions. Thus, it is possible to prevent a decrease in bonding strength near the engine mounting flange.

[0010] The invention according to claim 2 provides the above-described claim 1.
In addition to the configuration of the invention described in the above, in the pressing direction of a portion corresponding to the inclined portion in a welding margin set before welding at least one of the first and second joining members along the joining line. According to this configuration, the welding margin in the direction along the pressing line is set to be larger than the welding margin in the direction along the pressing direction of the remaining portion of the joining line other than the inclined portion. When the second joining members are pressed and welded to each other, the portions corresponding to the inclined portions of the first and second joining members come into contact with other portions first, so that the inclined portions are quickly or A large amount of welding is performed, and the joining strength near the engine mounting flange can be further increased.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect of the present invention, the inclined portion is inclined so as to be located at a lower position toward the engine mounting flange. Characteristically, according to such a configuration, it is possible to support the second joining member over the entire circumference of the joining line with the mold on the second joining member side. On the other hand, in the mold on the first joining member side, in order to prevent interference with a fuel injection valve or a fuel rail attaching portion disposed above the engine attaching flange, a part of the inclined portion of the joining line is prevented. Although it is difficult to support the first joint member, the present invention is based on the premise that it is difficult to make a reinforcement backup at a part of the inclined portion due to the overlap between the tubular portion and the inclined portion provided in the first joining member. The present invention is directed to an intake manifold, and there is no problem because the configuration of claim 1 or 2 compensates for the inability to support a part of the inclined portion. In addition, at the time of a vehicle collision, the inclined portion is hardly damaged by members such as the fuel rail disposed above the engine mounting flange.

According to a fourth aspect of the present invention, in manufacturing the vehicle intake manifold according to any one of the first to third aspects, a first mold on a first joining member side and a second mold are provided.
Along the joining line, the first and second joining members are pressed between the second mold on the joining member side and the first and second joining members while the inner surface of the portion corresponding to the inclined portion is not restrained. According to this manufacturing method, the joining strength of the inclined portion is reduced because the inclined portion of the joining line cannot receive effective reinforcing backup at the time of welding. In view of the fact that it can be avoided by any one of claims 1 to 3, it is possible to prevent the mold structure from being complicated by supporting the inner surface side at the portion corresponding to the inclined portion with a mold or the like. In addition, vibration welding can be performed with a mold device having a simple structure as in the related art.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on one embodiment of the present invention shown in the attached drawings.

1 to 8 show one embodiment of the present invention. FIG. 1 is a perspective view of an intake passage structure and a throttle body, FIG. 2 is a side view of the intake passage structure, and FIG. 2
FIG. 4 is a sectional view taken along line 4-4 of FIG. 3, and FIG.
FIG. 6 is an enlarged cross-sectional view of the joining member taken along the line 5-5 in FIG. 2; FIG. 6 is an enlarged cross-sectional view along the line 6-6 in FIG. 2; 7B is a view showing a state after welding, FIG. 7 is an enlarged sectional view taken along line 7-7 in FIG. 3, FIG. 7A is a view showing a state before welding, and FIG. 7B is a state after welding. FIGS. 8A and 8B are diagrams showing a manufacturing process of the intake passage structure, wherein FIG. 8A is a diagram showing a manufacturing state of the intake manifold, and FIG. 8B is a diagram showing a manufacturing state of the intake passage structure.

1 to 3, a throttle body 11 is attached to an intake passage structure 14 integrally having a surge tank 12 and an intake manifold 13 for connecting a four-cylinder engine (not shown) and the surge tank 12. The intake passage structure 14 is formed by first, second, and third joining members 15, 16, 17 made of synthetic resin being vibration-welded to each other.

The throttle body 11 has a cylindrical shape extending vertically and is connected to the center of the upper surface of the first joining member 15. A butterfly type throttle valve (not shown) for controlling the amount of air flowing through the throttle body 11 is provided. The throttle shaft 11 is fixed to a valve shaft 18 rotatably supported by the throttle body 11, and a throttle drum 19 is attached to a protruding end of the valve shaft 18 from the throttle body 11.

Referring to FIGS. 4 and 5, a connecting cylinder 15a for connecting the throttle body 11 is integrally provided at the center of the first joining member 15, and the surge tank 12 is provided with a connecting cylinder 15a. , First, second and third joining members 1
5, 16 and 17 form an intake chamber 20 connected to the connecting cylinder 15a.

A plurality of intake manifolds 13 are arranged in parallel in the horizontal direction so as to be arranged, for example, in pairs on both sides of the throttle body 11 and the connection cylinder portion 15a, and one end of which is commonly connected to the surge tank 12, for example. Four branch pipes 21A, 21B, 21C, 21D
Is connected to the engine mounting flange 22 for mounting to the engine in common and integrally.

The branch pipe 21A has one end connected to the surge tank 12 and rises upward.
A curved tube portion 24 having one end connected to the other end of the third tube 3 and a second straight tube portion 25 having one end connected to the other end of the curved tube portion 24 and extending substantially horizontally, and has a vertical plane. Branch pipe 2 to
The projection of 1A has a shape bent at approximately 90 degrees. The other branch pipes 21B, 21C, and 21D are also the same as the branch pipe 21A.
And the projection of each of the branch pipes 21B to 21D on a vertical plane also has a shape bent at substantially 90 degrees.

In each of the branch pipes 21A to 21D, an intake passage 26 is provided.
A, 26B, 26C, and 26D are formed, respectively, and the air introduced into the intake passage structure 14 from the throttle body 11 flows downward in the surge tank 12 as indicated by a broken arrow in FIG. Later, the air is inverted upward and divided into each of the intake passages 26A to 26D. Further, the air introduced into each of the intake passages 26A to 26D flows upward and then changes the flow direction by approximately 90 degrees and flows substantially horizontally toward the engine.

On the other hand, the engine mounting flange 22 has passage holes 27A, 27B, 27 for connecting the intake passages 26A to 26D to respective intake ports (not shown) of the engine.
C and 27D are provided individually corresponding to the respective intake passages 26A to 26D. As shown in FIG. 1, fuel injection valves 28 for supplying fuel to each intake port of the engine are mounted on the engine mounting flange 22, and a fuel rail is provided on each of the fuel injection valves 28. 29 are connected in common. On the upper part of the engine mounting flange 22, mounting portions 30, 30... For mounting the fuel injection valves 28, 28. 31 (see FIG. 2) are provided integrally.

Such an intake manifold 13 has a first
And the second joining members 15 and 16 are welded to each other at a joining line 32 connected in a loop shape. The first joining member 15 is integrally provided with an engine mounting flange 22. Each branch pipe 21A ~
21D and a part of the upper part of the surge tank 12.
The lower part of A to 21D and the main part of the surge tank 12 are formed.

In FIG. 6A, the first joining member 15
A joining flange 33 is formed integrally with the joining line 32 along the entire lower end thereof, and a ridge 34 having a flat joining surface 34a at the front end surface is formed at the center in the width direction of the joining flange 33. They are integrally provided so as to project toward the second joining member 16.

On the other hand, a joining flange 35 facing the joining flange 33 of the first joining member 16 is integrally formed around the entire upper end of the second joining member 16. A welding projection 36 corresponding to the joining surface 34a of the ridge 34 is integrally provided at the center in the width direction so as to project toward the second joining member 15 side. It is set narrower than the article. In addition, regulating wall portions 37 and 38 projecting toward the first joining member 15 are integrally provided on the entire periphery of the joining flange portion 35 of the second joining member 16 so as to sandwich the welding projection 36 from inside and outside. Can be

When the first and second joining members 15, 16 are welded to each other, the first and second joining members 15, 16 are welded to each other.
For example, by pressing the first joining member 15 in the pressing direction 39 toward the second joining member 16 in order to mutually press the joints 16, the tip of the welding projection 36 is joined to the joining surface of the ridge 34. In a state in which the first joining member 15 and the second joining member 15 and 16 are in contact with each other,
5 is vibrated at high speed. As a result, the tip of the welding projection 36 is vibration-welded to the ridge 34 as shown in FIG. 6B by frictional heat generated between the tip of the welding projection 36 and the joining surface 34a. 1st and 2nd joining members 1
The entire circumferences of 5 and 16 are joined along a joining line 32 which continues in a loop.

The two regulating walls 3 of the second joining member 16
The joining members 15, 16 have their distal ends close to and opposed to the joining flange 33 of the first joining member 15.
In addition to serving as a guide for stopping the vibration welding process in a state where the welding and joining have progressed, the first and second burrs generated by the vibration welding of the tip of the welding protrusion 36 to the joining surface 34a. It functions to prevent the inside of the two joining members 15 and 16, that is, the inside of the intake manifold 13, from outside.

The first and second joining members 15,
The 16 connecting lines 32 are used to connect the engine mounting flanges 2.
In the vicinity of 2, there is an inclined portion 32a which is arranged at substantially half the circumference of each of the branch pipes 21A to 21D so as to be inclined at an angle α with respect to the pressing direction 39 and is connected in a loop.
Since the engine mounting flange 22 is provided integrally with the joining member 15, the inclined portions 32 a are inclined so as to be located at lower positions toward the engine mounting flange 22.

Even in the inclined portions 32a, FIG.
As shown in (a), the first joining member 15 is provided integrally with a ridge 34 ′ connected to the ridge 34 so as to protrude toward the second joining member 16. The member 16 includes a welding projection 3 connected to the welding projection 36.
7 'and the regulating wall portions 37' and 38 'connected to the regulating wall portions 37 and 38 are integrally provided so as to protrude toward the first joining member 15 side.
As shown in (b), it is vibration-welded to the ridge 34 '.

By the way, the joining line 3 of the first and second joining members 15, 15 constituting the intake manifold 13
It is necessary that the joint along 2 has a sufficient joint strength to withstand the internal pressure, and a fuel rail 29 and the like are arranged near the flange 22 near the engine mounting flange 22 in the joint. In view of the above, it is necessary to maintain sufficient joining strength and rigidity. However, if the welding allowance of the first and second joining members 15 and 16 is set substantially uniformly over the entire area of the joining line 32, The joining strength of the inclined portions 32a in the joining line 32 is lower than that of other portions, and the necessary joining strength cannot be obtained. That is, the inclined portions 32a are arranged on substantially half the circumference of the branch pipes 21 while being inclined with respect to the pressing direction 39 when the two joining members 15, 16 are mutually pressed during welding. The cylindrical portions 15b provided in the first joining member 15 in advance so as to constitute the entire inner circumference of the passages 26A to 26D, and a part of the inclined portions 32a are positioned in the pressing direction 39 during welding. And the first and second joining members 15, 1
6 are mutually pressed, it is difficult to receive a portion corresponding to the inclined portions 32a on the first joining member 15 side with a mold, and the inclined portions 32a of the joining line 32 are effective at the time of welding. This is because no reinforcement backup is available.

Therefore, the welding projection 3 of the second joining member 16
6, 36 ', the welding margin W' in the direction orthogonal to the pressing direction 39 of the welding projection 36 'at the portion corresponding to the inclined portion 32a is set to the inclination of the joining line 32. The welding margin W of the welding projection 36 in the remaining portion excluding the portions 32a... In the direction orthogonal to the pressing direction 39 is set to be larger. Thereby, the first and second joining members 1
When the first and second members 15 and 16 are welded by pressing each other, the amount of welding at the portions corresponding to the inclined portions 32a of the first and second joining members 15 and 16 is larger than at other portions.

The welding projections 36 of the second joining member 16
36 'of the welding allowance set before welding.
The pressing direction 39 of the welding projection 36 'at the portion corresponding to 2a ...
The welding margin L 'along the inclined line 32a of the joining line 32
The pressing direction 39 of the welding projection 36 at the remaining portion except for
Is set larger than the welding allowance L along. Thus, when the first and second joining members 15 and 16 are mutually pressed and welded, the portions corresponding to the inclined portions 32a of the first and second joining members 15 and 16 are attached to other portions. They will come in contact first.

When the first and second joining members 15 and 16 are welded and joined to each other, as shown in FIG. 8A, the first mold 40 on the first joining member 15 side and the first The first and second joints are vibrated by vibrating the first mold 40 while pressing the first and second joining members 15 and 16 between the second mold 41 and the second joining member 16 on the side of the second joining member 16. Members 15, 16
Are vibrated and welded along the joining line 32. At this time, the inclined portions 32a of the joining line 32 cannot be effectively backed up by the first mold 40, but the inner surface at the portion corresponding to the inclined portions 32a must be supported by a mold or the like. And remain unconstrained.

The first and second joining members 15, 16
An intake manifold 13 formed by mutual joining of
The third joining member 17 is, as shown in FIG. 8B, an intake manifold between a third mold 42 on the intake manifold 13 side and a fourth mold 43 on the third joining member 17 side. 13
The third mold 42 is vibrated and welded by vibrating the third mold 42 while pressing the third joining member 17 therebetween, thereby completing the production of the intake passage structure 14.

Next, the operation of this embodiment will be described. The inclined portion 32 of the welding margin set before welding by the first joining member 15 along the loop-shaped joining line 32 is explained.
The welding margin W ′ of the portion corresponding to the part a corresponding to the direction perpendicular to the pressing direction 39 is perpendicular to the pressing direction 39 of the welding projection 36 at the remaining part except for the inclined part 32 a of the joining line 32. Is set to be larger than the welding margin W. Accordingly, when the first and second joining members 15 and 16 are mutually pressed and welded, the amount of welding at the portions corresponding to the inclined portions 32a of the first and second joining members 15 and 16 is different. Larger than the part. Therefore, of the first and second joining members 15 and 16, the cylindrical portion 15 of the first joining member 15 is provided.
inclined portion 32a at a portion overlapping with a in the pressing direction 39
The inclined portion 32 due to the absence of the reinforcing backup
are bent, a large amount of the inclined portions 32a are welded by the difference (W'-W) from other portions of the welding allowance along the direction orthogonal to the pressing direction 39. Whether the bonding strength is substantially uniform over the entire circumference of the bonding line 32,
The joining strength of the inclined portions 32a can be made larger than that of the other portions, and a decrease in joining strength near the engine mounting flange 22 can be prevented.

In the welding margin set before welding by the first joining member 15 along the joining line 32, the inclined portion 32a
The welding margin L 'in the direction corresponding to the pressing direction 39 along the pressing direction 39 is set to be larger than the welding margin L along the pressing direction 39 in the remaining portion of the joining line 32 except for the inclined portions 32a. Therefore, at the time of welding, the portions corresponding to the inclined portions 32a of the first and second joining members 15, 16 come into contact with other portions first. Therefore, even if the inclined portions 32a are bent at the time of welding, the inclined portions 3a by the difference (L'-L) of the welding margin along the pressing direction 39 with other parts.
2a are welded earlier or more frequently, and when the predetermined amount of welding at the other portion is completed, the amount of welding of the inclined portions 32a is equal to or greater than the amount of welding of the other portion. Become. As a result, the joining strength in the vicinity of the engine mounting flange 22 can be further improved, in addition to the strength improving effect due to the difference in the welding allowance (W′−W) in the direction perpendicular to the pressing direction 39.

Moreover, since the inclined portions 32a are inclined so as to be located at a lower position toward the engine mounting flange 22, the second mold 4 on the second joining member 16 side.
1 and the second joining member 1 over the entire circumference of the joining line 32.
6 can be supported. On the other hand, the first mold 40 on the side of the first joining member 15 prevents interference with the fuel injection valves 28... Disposed above the engine mounting flange 22 and the mounting portions 30. Therefore, it is difficult to support a part of the inclined portions 32a of the joining line 32. However, in the first place, according to the present invention, the cylindrical portions 15b of the first joining member 15 and the inclined portions 32a overlap. Vehicle intake manifold 13 on the premise that reinforcement backup is difficult at a part of the inclined portions 32a.
There is no problem because the difference in the welding margin compensates for the inability to support a part of the inclined portions 32a. Moreover, at the time of a vehicle collision, the inclined portions 32a are hardly damaged by members such as the fuel rail 29 disposed above the engine mounting flange 22.

Further, the first and second joining members 15, 1
6, the inner surface of the portion corresponding to the inclined portion 32a is not restrained at the time of welding and joining, so that the inner surface at the portion corresponding to the inclined portion 32a is supported by a mold or the like. Can be prevented from becoming complicated, and vibration welding can be performed with a mold device having a simple structure as in the past.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible to do.

[0039]

As described above, according to the first aspect of the present invention, even if the inclined portion is bent when the first and second joining members are pressurized and welded to each other, the first and second joining members are connected to other portions. The inclined portion is welded more by the difference in the welding margin along the direction orthogonal to the pressing direction, and the joining strength is made substantially uniform over the entire circumference of the joining line, or the joining strength of the inclined portion is reduced. It can be larger than other parts, and it is possible to prevent a decrease in bonding strength near the engine mounting flange.

According to the second aspect of the present invention, when the first and second joining members are mutually pressed and welded, a portion corresponding to the inclined portion of the first and second joining members may be different. And the welded portion is welded earlier or more frequently, so that the joint strength near the engine mounting flange can be further increased.

According to the third aspect of the present invention, the second joining member is supported over the entire periphery of the joining line by the mold on the second joining member side while compensating for the inability to support a part of the inclined portion. This makes it possible to prevent the inclined portion from being damaged by a member such as a fuel rail disposed above the engine mounting flange at the time of a vehicle collision.

According to the fourth aspect of the present invention, it is possible to prevent the mold structure from becoming complicated, and to perform vibration welding with a mold device having a simple structure as in the related art.

[Brief description of the drawings]

FIG. 1 is a perspective view of an intake passage structure and a throttle body.

FIG. 2 is a side view of the intake passage structure.

FIG. 3 is a view as viewed in the direction of arrow 3 in FIG. 2;

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

FIG. 5 is a cross-sectional view of the second joining member viewed from a direction along line 5-5 in FIG. 2;

6 is an enlarged sectional view taken along line 6-6 in FIG. 2, wherein (a) is a view showing a state before welding and (b) is a view showing a state after welding.

FIGS. 7A and 7B are enlarged sectional views taken along line 7-7 in FIG. 3, wherein FIG. 7A is a view showing a state before welding and FIG. 7B is a view showing a state after welding.

8A and 8B are diagrams illustrating a process of manufacturing the intake passage structure, wherein FIG. 8A is a diagram illustrating a manufacturing state of the intake manifold, and FIG.
FIG. 4 is a view showing a state of manufacturing the intake passage structure.

[Explanation of symbols]

 12 ... Surge tank 13 ... Intake manifold 15 ... First joining member 15b ... Cylinder 16 ... Second joining member 21A, 21B, 21C, 21D ... Branch pipe 22 ..Flange for engine attachment 32 ... Junction line 32a ... Inclination 39 ... Pressing direction 40 ... First mold 41 ... Second mold

Claims (4)

[Claims] 1. A plurality of branch pipes (21A) having a shape projected on a vertical plane bent at approximately 90 degrees and having one end commonly connected to a surge tank (12) and arranged in parallel in a horizontal direction. , 21B, 21C, 21D) and an engine mounting flange (22) commonly connected to the other ends of the branch pipes (21A to 21D), and the engine mounting flange (22) is integrally provided. Each branch pipe (21A-2
1D), a first joining member (15) made of a synthetic resin and a second joining member (16) made of a synthetic resin that constitutes the rest of each of the branch pipes (21A to 21D). Each branch pipe (21A to 2A) is inclined with respect to the pressing direction (39) when the two joining members (15, 16) are pressed together during welding.
1D) In a vehicle intake manifold having an inclined portion (32a) arranged on substantially the other half side on the other end side and welded to each other by a joining line (32) connected in a loop, the joining line (32) Along with at least one of the first and second joining members (15, 16), a portion corresponding to the inclined portion (32a) in a welding margin set before welding is orthogonal to the pressing direction (39). The welding margin in the direction is set to be larger than the welding margin in the direction orthogonal to the pressing direction (39) of the remaining portion of the joining line (32) except for the inclined portion (32a). Intake manifold for vehicles. 2. The inclined portion (32a) of a welding margin set before welding along at least one of the first and second joining members (15, 16) along the joining line (32).
The welding margin in the direction along the pressing direction (39) of the portion corresponding to the inclined portion (32) of the joining line (32)
2. The intake manifold for a vehicle according to claim 1, wherein a welding margin in a direction along the pressing direction (39) of the remaining portion excluding a) is set. 3. The intake manifold for a vehicle according to claim 1, wherein the inclined portion (32a) is inclined so as to be located at a lower position toward the engine mounting flange (22). 4. A first mold (40) on the first joining member (15) side and a second joining member for producing the vehicle intake manifold according to claim 1. Between the second mold (41) on the (16) side and the inner surface side of the portion corresponding to the inclined portion (32a) is unconstrained,
The first and second joining members (15, 16) are vibration-welded along the joining line (32) in a state where the first and second joining members (15, 16) are sandwiched and pressed. Of manufacturing a vehicle intake manifold.