JP2010001838A - Exhaust manifold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust manifold which can be easily manufactured. <P>SOLUTION: This exhaust manifold is provided with a first-fourth branch pipe part 11-14 connected to a first-fourth exhaust port 1-4, and a collecting part 16 to which the first-fourth branch pipe part 11-14 are connected, and is attached to a cylinder head S through a flange member 18. Flange parts 11a-14a are formed at cylinder head S side of the first-fourth branch pipe part 11-14. Through holes 21-24 communicating to the first-fourth exhaust port 1-4 are formed on the flange member 18, and hollow parts 26-29 storing the flange parts 11a-14a are formed at the cylinder head S side with connected the through-holes 21-24. The flange member 18 is divided into at least two and the through-holes 21-24 are formed when the two are butted. The divided flange member 18 are butted and welded under a condition where the first-fourth branch pipe part 11-14 are inserted in the through-holes 21-24 after welding the first-fourth branch pipe part 11-14 are welded to the collecting part 16. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an exhaust manifold in which a branch pipe portion connected to an exhaust port is attached to a cylinder head via a flange.

Conventionally, in an exhaust manifold, when a plurality of branch pipe parts and a flange member are welded together, a thermal expansion / contraction difference occurs due to a temperature difference between the branch pipe part or the gathering part and the flange member, and the branch pipe part and the flange member are There was a problem that a crack occurred between them or the flange member was bent. Therefore, as disclosed in Patent Document 1, the branch pipe portion is inserted into the through hole of the flange member, and a slide collar having a flange-like flange portion formed on the end of the branch pipe portion is integrally welded. The flange member is formed with a recess for accommodating the flange portion, and the flange member is fixed to the cylinder head, and the outer periphery of the flange portion and the recess of the flange member, and the outer periphery of the branch pipe portion and the penetration of the flange member are formed. A device in which a gap is formed between the holes is known.
JP 2004-150385 A

  However, in such a conventional apparatus, when the exhaust manifold is attached to the internal combustion engine, there are cases where the length of the branch pipe portion cannot be increased due to the relationship between surrounding devices and parts. In such a case, as shown in FIG. 10, the slide collar 104 is inserted into the through hole 102 of the flange member 100, and the flange portion 108 of the slide collar 104 is inserted into the concave portion 106 of the flange member 100. The branch pipe portion 112 attached to the collective portion 110 is inserted into the slide collar 104 and welded, but the gap between the flange member 100 and the collective portion 110 is narrow, and no welding torch enters between them. Therefore, for welding the slide collar 104 and the branch pipe portion 112, the welding torch 114 must be inserted into the slide collar 104 and welded from the inner peripheral surface side of the slide collar 104.

  When welding from the inner peripheral surface side, spatter during welding adheres to the inside of the collecting portion 110 and the branch pipe portion 112, and when the internal combustion engine is operated, the spatter may enter the internal combustion engine and cause a failure. is there. For this reason, welding requires TIG welding that does not generate spatter, and in order to obtain good welding quality that does not generate spatter due to TIG welding or the like, strict management of welding conditions is required. There was a problem that a great deal of man-hours was required and the production was complicated.

  An object of the present invention is to provide an exhaust manifold that is easy to manufacture.

In order to achieve this problem, the present invention has taken the following measures in order to solve the problem. That is,
In an exhaust manifold, comprising: a branch pipe part connected to an exhaust port of a cylinder head of an internal combustion engine; and a collecting part to which the branch pipe part is connected, wherein the branch pipe part is attached to the cylinder head via a flange member ,
In the branch pipe part, a flange is formed at the cylinder head side end of the branch pipe part,
The flange member is formed with a through hole communicating with the exhaust port, and a recessed portion accommodating the flange portion on the cylinder head side connected to the through hole,
And when the said flange member is divided | segmented into at least two and butt | matched, the said through-hole is formed,
The exhaust manifold is characterized in that, after the branch pipe portion is welded to the collecting portion, the divided flange member is butted with the branch pipe portion inserted into the through hole.

  The flange member may be divided into two by a curved dividing line. At that time, the flange member is provided with a plurality of branch pipe portions, and the flange member is divided into two at the dividing line extending over all the through holes, and is divided with the branch pipe portions inserted into all the through holes. It is good also as a structure which faced the said flange member. Further, a recess is formed along the dividing line on the cylinder head side of the flange member, the flange member divided in a state where the branch pipe portion is inserted into the through hole is abutted, and along the dividing line It is good also as a structure welded. It is good also as a structure which provided the clearance gap between the said through-hole and the said branch pipe part.

  In the exhaust manifold of the present invention, when the branch pipe part is welded to the collecting part, welding is performed outside the branch pipe part. Therefore, even if spatter or the like occurs, the spatter is generated inside the branch pipe part or the collecting part. There is little possibility of entering, and it is easy to set the welding conditions and the like, and it becomes easy to manage the welding conditions, and the manufacturing is easy.

  Further, when the flange member is divided by a curved dividing line, positioning when the divided flange members are brought into contact with each other becomes easy. If a depression is formed along the dividing line on the cylinder head side of the flange member, the welding beat can be prevented from popping out.

The best mode for carrying out the present invention will be described below in detail with reference to the drawings.
As shown in FIG. 1, S is a cylinder head of an internal combustion engine. In this embodiment, S is a cylinder head S of 4 cylinders or a cylinder head S of 4 cylinders on one side of a V-type 8-cylinder internal combustion engine. In the cylinder head S, first to fourth exhaust ports 1 to 4 for four cylinders are arranged in a row.

  An exhaust manifold 10 is attached to the cylinder head S. The exhaust manifold 10 includes first to fourth branch pipe portions 11 to 14, a collecting portion 16, and a flange member 18. The first to fourth branch pipe portions 11 to 14 are arranged in a line corresponding to the first to fourth exhaust ports 1 to 4, and the first to fourth branch pipe portions 11 to 14 are a hollow assembly. Each unit 16 is connected and assembled.

  The flange member 18 is formed with through holes 21 to 24 into which the four first to fourth branch pipe portions 11 to 14 are inserted, respectively. Each of the through holes 21 to 24 is provided at a position communicating with the first to fourth exhaust ports 1 to 4 when the flange member 18 is attached to the cylinder head S.

  A gap is formed between the outer circumferences of the first to fourth branch pipe portions 11 to 14 and the inner circumferences of the through holes 21 to 24. The size of the gap may be determined by experiments or the like according to the thermal expansion / contraction difference between the first to fourth branch pipe portions 11 to 14 and the collecting portion 16 and the flange member 18.

  On the other hand, the first to fourth branch pipe portions 11 to 14 are integrally formed with flange portions 11a to 14a having tips that are widened radially outward on the cylinder head S side end. Concave portions 26 to 29 are formed on the cylinder head S side of the flange member 18 so as to be connected to the through holes 21 to 24. The recesses 26 to 29 are formed in a size that can accommodate the flanges 11a to 14a of the first to fourth branch pipe portions 11 to 14, and the outer periphery of the flanges 11a to 14a and the inner periphery of the recesses 26 to 29. A gap is formed between them. The size of the gap may be determined by experiment or the like according to the thermal expansion / contraction difference between the first to fourth branch pipe portions 11 to 14 and the collecting portion 16 and the flange member 18. The flange member 18 has a plurality of attachment holes 30 formed therein.

  Moreover, in this embodiment, the 1st branch pipe part 11 is inserted in the front-end | tip of the tubular gathering part 16, and is welded by welding. The first branch pipe portion 11 is welded to the collecting portion 16 in a state where the flange member 18 is not attached. Further, as shown in FIG. 2, the end opposite to the flange portion 14 a is widened to the fourth branch pipe portion 14 radially outward in a flange shape, and is in close contact with the outer peripheral shape of the collecting portion 16. A mounting portion 14b is formed.

  The attachment portion 14b of the fourth branch pipe portion 14 is in close contact with the outer periphery of the assembly portion 16, the periphery of the attachment portion 14b is welded by the welding torch 114, and the fourth branch pipe portion 14 is attached to the assembly portion 16 by welding. Yes. Welding is performed in a state where the flange member 18 is not attached, and welding is performed along the outer periphery of the attachment portion 14b. Therefore, even if spatter or the like occurs, the spatter or the like is less likely to enter the fourth branch pipe portion 14 or the gathering portion 16, and it is easy to set the welding conditions and the management of the welding conditions. Welding work is easy.

  Similarly, the other second branch pipe portion 12 and the third branch pipe portion 13 are respectively formed with attachment portions 12b and 13b, and welding is performed along the outer periphery of the attachment portions 12b and 13b. It is welded to the gathering portion 16.

  The connection of the fourth branch pipe portion 14 to the collective portion 16 is not limited to the case where the attachment portion 14b is formed, but as shown in FIG. 3, the cylindrical portion 32 is formed in the collective portion 16 by burring or the like. The fourth branch pipe part 14 may be inserted into the cylindrical part 32, and the edge of the cylindrical part 32 may be welded all around by the welding torch 114 to weld the fourth branch pipe part 14 and the collecting part 16.

  Even in this case, welding is performed on the outer peripheral side of the fourth branch pipe portion 14. Therefore, even if spatter or the like occurs, the spatter or the like is less likely to enter the fourth branch pipe portion 14 or the gathering portion 16, and it is easy to set the welding conditions and the management of the welding conditions. Welding work is easy.

  On the other hand, as shown in FIG. 4, the flange member 18 is formed by abutting an upper half 18a and a lower half 18b which are divided into two. In the present embodiment, the upper half 18a and the lower half 18b are divided along a curved dividing line 34, and for example, the first to fourth branch pipe portions 11 to 14 are respectively connected to the upper half. When the lower half body 18b is abutted after being inserted into the half through holes 21 to 24 on the body 18a side, the first to fourth branch pipe portions 11 to 14 are inserted into the respective through holes 21 to 24. Thus, each through-hole 21-24 is divided | segmented into the half.

  Indentations 36 and 38 are formed along the dividing line 34 on the cylinder head S side of the upper half 18a and the lower half 18b. When the upper half 18a and the lower half 18b are abutted by the dividing line 34, as shown in FIG. 7, the depressions 36 and 38 become one, and the dividing line 34 is formed at the bottom in the depressions 36 and 38. It is formed to be arranged.

  The dividing line 34 is formed in a curved line that also serves as a positioning so that the through holes 21 to 24 are formed when the upper half 18a and the lower half 18b are brought into contact with each other. That is, the curve is determined so that the longitudinal position of the gathering portion 16 is determined when the dividing line 34 between the upper half 18a and the lower half 18b is abutted.

  As shown in FIGS. 5 and 6, after the first to fourth branch pipe parts 11 to 14 and the collecting part 16 are integrally welded, the upper half 18 a and the lower half 18 b of the flange member 18 are The first to fourth branch pipe portions 11 to 14 are put together so as to sandwich each other. In that case, it butt | matches so that it may be in the state inserted in the 1st-4th branch pipe parts 11-14 to each through-hole 21-24.

  Next, as shown in FIG. 7, from the cylinder head S side, along the dividing line 34 in the recesses 36 and 38 of the upper half 18a and the lower half 18b, the upper half 18a and the lower half 18b Are integrated by welding. Since welding is performed in the depressions 36 and 38, the welding beat 40 is welded so that the welding beat 40 does not protrude from the depressions 36 and 38 even when the welding beat 40 rises. 40 does not get in the way.

Next, the operation of the exhaust manifold of the present embodiment described above will be described.
First, when the exhaust manifold 10 is assembled to the cylinder head S, bolts (not shown) are inserted into the mounting holes 30 to fix the flange member 18 to the cylinder head S. A downstream exhaust pipe (not shown) is connected to the collecting portion 16.

  When the exhaust gas is discharged from the first to fourth exhaust ports 1 to 4 along with the operation of the internal combustion engine, it flows into the collecting portion 16 through the first to fourth branch pipe portions 11 to 14, and the collecting portion 16 Through the exhaust pipe (not shown) on the downstream side.

  At that time, the temperature of the exhaust manifold 10 rises. Since the flange member 18 is in close contact with the cylinder head S, its temperature rise is small and the temperature rise of the gathering portion 16 is large. In the exhaust manifold 10, a temperature difference is generated between the flange member 18 and the gathering portion 16, thereby causing a thermal expansion / contraction difference. The thermal expansion / contraction difference is absorbed by the gap.

  As described above, in the exhaust manifold 10 of the present embodiment, the first to fourth branch pipe portions 11 to 14 are welded to the assembly portion 16. At that time, since welding is performed outside the first to fourth branch pipe portions 11 to 14, even if spatter or the like occurs, the spatter or the like is not generated in the first to fourth branch pipe portions 11 to 14 or the collecting portion 16. There is little risk of entering the inside, setting of welding conditions and the like are easy, and management of the welding conditions becomes easy, and welding work is easy.

  After the first to fourth branch pipe portions 11 to 14 are welded to the assembly portion 16, the first half to the fourth branch pipe are formed by the upper half 18a and the lower half 18b of the flange member 18 divided into two parts. The upper half 18a and the lower half 18b are abutted so as to sandwich the portions 11-14. The upper half body 18 a and the lower half body 18 b are welded along the dividing line 34 in a state where the first to fourth branch pipe portions 11 to 14 are inserted into the through holes 21 to 24. Therefore, the welding operation is facilitated and the manufacture is facilitated.

  In this embodiment, the upper half 18a and the lower half 18b are welded along the dividing line 34 in the recesses 36 and 38 of the upper half 18a and the lower half 18b, and the upper half 18a and the lower half 18b are integrated. Not limited to this, as shown in FIG. 8, a convex portion 42 and a concave portion 44 that are fitted to each other along the dividing line 34 are formed, and the upper half body 18 a and the lower half body 18 b are abutted to each other. 44, after fitting, a bolt (not shown) may be inserted into each mounting hole 30 to weld the flange member 18 to the cylinder head S without welding.

  Alternatively, as shown in FIG. 9, overlapping portions 46 and 48 that overlap each other along the dividing line 34 are formed in the upper half 18a and the lower half 18b, and the upper half 18a and the lower half 18b are abutted, After overlapping the overlapping portions 46 and 48, the flange member 18 may be fixed to the cylinder head S by inserting a bolt (not shown) into each mounting hole 30 without welding.

  The internal combustion engine is not limited to the case of four cylinders, and may be three cylinders or less, or may be similarly implemented with five cylinders or more. Moreover, although the case where the 1st-4th branch pipe parts 11-14 were attached to the one flange member 18 was taken as an example, not only this but the 1st, 2nd branch pipe parts 11 and 12 are made into one flange. It can also be implemented by attaching to the member and attaching the third and fourth branch pipe portions 13 and 14 to one flange member. Further, the present invention can be implemented by attaching one flange member to each of the first to fourth branch pipe portions 11 to 14.

  The present invention is not limited to such embodiments as described above, and can be implemented in various modes without departing from the gist of the present invention.

It is an enlarged front view which shows a part of exhaust manifold as one Embodiment of this invention in a cross section. It is explanatory drawing of the connection by welding with the 4th branch pipe and gathering part of this embodiment. It is explanatory drawing of the connection by welding with the 4th branch pipe and assembly part as other embodiment. It is the rear view which looked at the flange member of this embodiment from the cylinder head side. It is explanatory drawing of the state which butts the upper half body and lower half body of a flange member on both sides of the branch pipe part of this embodiment. It is the rear view seen from the cylinder head side of the exhaust manifold of this embodiment. It is an expanded sectional view of the hollow of the flange member of this embodiment. It is an expanded sectional view orthogonal to the parting line of the flange member as another embodiment. It is an expanded sectional view orthogonal to the dividing line of the flange member as other embodiments. It is explanatory drawing of the connection by welding of the conventional slide collar and a branch pipe part.

Explanation of symbols

16, 110 ... Collecting part 18, 100 ... Flange member 18a ... Upper half 18b ... Lower half 21 to 24, 102 ... Through hole 26 to 29, 106 ... Recess 30 ... Mounting hole 32 ... Cylindrical part 34 ... Dividing line 36 , 38 ... depression 40 ... welding beat S ... cylinder head

Claims (5)

In an exhaust manifold, comprising: a branch pipe part connected to an exhaust port of a cylinder head of an internal combustion engine; and a collecting part to which the branch pipe part is connected, wherein the branch pipe part is attached to the cylinder head via a flange member ,
In the branch pipe part, a flange is formed at the cylinder head side end of the branch pipe part,
The flange member is formed with a through hole communicating with the exhaust port, and a recessed portion accommodating the flange portion on the cylinder head side connected to the through hole,
And when the said flange member is divided | segmented into at least two and butt | matched, the said through-hole is formed,
An exhaust manifold characterized in that, after the branch pipe part is welded to the collecting part, the divided flange member is butted with the branch pipe part being inserted into the through hole. The exhaust manifold according to claim 1, wherein the flange member is divided into two by a curved dividing line. The flange member is provided with a plurality of branch pipe portions, and the flange member is divided into two at the dividing line extending over all the through holes, and is divided with the branch pipe portions inserted into all the through holes, respectively. The exhaust manifold according to claim 2, wherein: On the cylinder head side of the flange member, a recess is formed along the dividing line, the flange member divided in a state where the branch pipe portion is inserted into the through hole is abutted, and welding is performed along the dividing line. The exhaust manifold according to any one of claims 2 and 3, wherein the exhaust manifold is formed. The exhaust manifold according to any one of claims 1 to 4, wherein a gap is provided between the through hole and the branch pipe portion.

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