JP2019210898A - Exhaust system component fastening structure - Google Patents

Abstract

To provide an exhaust system component fastening structure capable of improving in-planar distribution of fastening forces of a pair of flanges by improving a contact condition of a coupling to the pair of flanges.SOLUTION: An exhaust system component fastening structure comprises a coupling 30 for fastening and coupling a first flange 11 and a second flange 21 in a radial direction. When an angle obtained by subtracting a fastening inclination face angle φ defined by an angle formed by a first fastening inclination face 40 and a second fastening inclination face 41 of the coupling 30 from a total flange angle θ defined by a first flange inclination face 12 of the first flange 11 and a second flange inclination face 22 of the second flange 21 is designated as a differential angle α, the differential angle α at a predetermined portion in a range of ±90° when a direction at which a fastening force generation portion 36 is positioned with centers of the first and second flanges as centers is 180°, is larger than the differential angle α in other ranges.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an exhaust system component fastening structure. Specifically, the present invention relates to an exhaust system component fastening structure in which a fastening member is configured to fasten and fasten a first flange of a first exhaust system component and a second flange of a second exhaust system component in a radial direction.

Conventionally, there has been known a fastening structure in which a pair of flanges including a flange of a first exhaust system part and a flange of a second exhaust system part of an internal combustion engine are fastened in a radial direction by using a coupling as a fastening member. It has been.
In such a fastening structure, as shown in Patent Document 1, a pair of flanges are fastened by using a coupling having a structure in which ends of a plurality of arcuately connected members are connected by bolts. Fastening structures are known.

JP 2005-344580 A

  The fastening structure as shown in Patent Document 1 employs a structure that can be easily fastened by tightening one bolt, so that the contact state of the coupling with the pair of flanges is uneven depending on the location. There is a problem. Specifically, the contact force between the pair of flanges and the coupling is high at the bolt tightening portion, that is, around the portion where the fastening force is generated, and the contact force is low at other portions.

  This invention is made | formed in view of the said subject, The objective is improving the in-plane distribution of the fastening force of a pair of flanges by improving the contact state of the coupling with respect to a pair of flange. Another object is to provide an exhaust system component fastening structure.

(1) The present invention is a first exhaust system component (for example, a turbo housing 10 of a turbocharger) provided with a first flange inclined surface (for example, a first flange inclined surface 12). Provided on a flange (for example, the first flange 11) and a second exhaust system component (for example, the catalyst case 20) different from the first exhaust system component, a second flange inclined surface (for example, a second flange) A second flange (e.g., second flange 21) having a flange inclined surface 22),
A fastening force generation point (for example, a fastening force generation point 36), a first fastening inclined surface (for example, the first fastening inclined surface 40) opposed to the first flange inclined surface at the time of fastening, and the first at the time of fastening. A second fastening inclined surface (for example, the second fastening inclined surface 41) facing the flange inclined surface of the two flanges, and depending on the force generated at the place where the fastening force is generated, An exhaust system component fastening structure comprising: a fastening member (for example, coupling 30, 60, 70) that fastens and fastens the first and second flanges in a radial direction by a fastening inclined surface;
From the overall flange angle (for example, the overall flange angle θ) defined by the angle formed by the first flange inclined surface and the second flange inclined surface, the first fastening inclined surface and the second of the fastening member. When the angle obtained by subtracting the fastening inclined surface angle (for example, the fastening inclined surface angle φ) defined by the angle formed with the fastening inclined surface is a difference angle (for example, the differential angle α),
The difference angle at a predetermined portion within a range of ± 90 ° when the direction in which the fastening force generation point is located is 180 ° with respect to the centers of the first and second flanges is in another range. Is larger than the difference angle.

In the exhaust system component fastening structure according to the invention of (1), the first flange of the fastening member is determined from an overall flange angle defined by an angle formed by the first flange inclined surface and the second flange inclined surface. When the angle obtained by subtracting the fastening inclined surface angle defined by the angle formed by the fastening inclined surface and the second fastening inclined surface is a difference angle, the center of the first and second flanges is used as a reference, When the direction in which the fastening force generation point is located is 180 °, the difference angle in a predetermined portion within a range of ± 90 ° is larger than the difference angle in other ranges.
Therefore, the contact state of the fastening member with respect to the first and second flanges can be improved, and as a result, the in-plane distribution of the fastening force between the first and second flanges can be improved.

  (2) In the exhaust system component fastening structure according to (1), the overall flange angle in a predetermined portion within the range of ± 90 ° is set larger than the overall flange angle in the other range. The difference angle in the predetermined portion within the range of ± 90 ° is larger than the difference angle in the other ranges.

In the exhaust system component fastening structure according to the invention of (2), the overall flange angle in the predetermined portion within the range of ± 90 ° is set larger than the overall flange angle in the other range.
Therefore, the contact state of the fastening member with respect to the first and second flanges can be improved by devising the shape of the flange, and as a result, the in-plane distribution of the fastening force between the first and second flanges. Can be improved.

  (3) In the exhaust system component fastening structure according to (2), an angle formed by the first flange inclined surface and the flange end surface of the first flange is a first flange angle (for example, a first flange angle). θ1), and the angle formed between the second flange inclined surface and the flange end surface of the second flange is a second flange angle (for example, the second flange angle θ2), the total flange angle is: The first flange angle is defined by the sum of the first flange angle and the second flange angle, and the first flange angle and the second flange angle in a predetermined portion within the range of ± 90 ° are substantially equal.

In the exhaust system component fastening structure according to the invention of (3), the first flange angle and the second flange angle at a predetermined portion within the range of ± 90 ° are substantially equal.
Therefore, at the time of fastening, the fastening member can be pressed against the first and second flanges with a good balance.

  (4) The exhaust system component fastening structure according to any one of (2) to (3), further comprising a positioning portion for positioning rotational positions of the fastening member and the first and second flanges.

  The exhaust system component fastening structure according to the invention of (4) further includes a positioning portion for positioning the rotational position of the fastening member and the first and second flanges. The relative rotational positional relationship between the 180 ° position where the occurrence point is arranged and the ± 90 ° range where the overall flange angle θ is set to be large is always properly positioned. .

  (5) In the exhaust system component fastening structure according to (1), the fastening slope angle in a predetermined portion within the range of ± 90 ° is set smaller than the fastening slope angle in the other range. Accordingly, the difference angle in the predetermined portion within the range of ± 90 ° is larger than the difference angle in the other ranges.

  In the exhaust system component fastening structure according to the invention of (5), the fastening inclined surface angle in a predetermined portion within the range of ± 90 ° is set smaller than the fastening inclined surface angle in the other range.

  Therefore, the contact state of the fastening member with respect to the first and second flanges can be improved by devising the shape of the fastening member. As a result, the in-plane of the fastening force between the first and second flanges can be improved. Distribution can be improved.

  (6) In the exhaust system component fastening structure according to (5), the fastening member is disposed at the outer periphery of the first and second flanges at three or more outer periphery fastening members (for example, arcuate members). The fastening inclined surface angle of one or more outer peripheral fastening members provided within the range of ± 90 ° is set smaller than the fastening inclined surface angle of the other outer peripheral fastening members.

In the exhaust system component fastening structure according to the invention of (6), the fastening member includes three or more outer peripheral fastening members, and the fastening of the one or more outer peripheral fastening members provided within the range of ± 90 °. The inclined surface angle is set smaller than the fastening inclined surface angle of the other outer periphery fastening member.
Therefore, since the fastening inclined surface angle φ can be set for each member of the outer periphery fastening member, the fastening structure of the present invention can be easily configured.

  (7) In the exhaust system component fastening structure according to (1) to (6), the predetermined portion has a direction in which the fastening force generation location is located with reference to the centers of the first and second flanges. In the case of 180 °, it is provided in a range wider than ± 45 ° and narrower than ± 75 °.

In the exhaust system component fastening structure according to the invention of (7), the predetermined portion is in a case where the direction in which the fastening force generation point is located is 180 ° with reference to the centers of the first and second flanges. , And a range wider than ± 45 ° and narrower than ± 75 °.
Therefore, the in-plane distribution of the fastening force between the first and second flanges can be equalized more effectively.

  ADVANTAGE OF THE INVENTION According to this invention, the exhaust system component fastening structure which can improve in-plane distribution of the fastening force of a pair of flanges by improving the contact state of the coupling with respect to a pair of flange can be provided. .

It is the schematic which shows a part of exhaust system of the internal combustion engine which concerns on one Embodiment of this invention, and the fastening structure of exhaust system components. It is a figure which shows the coupling of the fastening structure which concerns on the said embodiment. It is a figure which shows typically the LL cross section in FIG. It is a figure which shows typically the MON cross section in FIG. It is the enlarged view to which the lower part vicinity of FIG. 4 was expanded. It is a graph which shows in-plane distribution of the fastening force of a pair of flanges in the fastening structure concerning one embodiment of the present invention. It is a figure which shows the modification of the said embodiment, and is a figure corresponding to FIG. It is a figure which shows the example of the other structure of a coupling in the fastening structure which concerns on the said embodiment. It is a figure which shows the example of the other structure of a coupling in the fastening structure which concerns on the said embodiment. It is a figure which shows a conventional structure, and is a figure corresponding to FIG. It is a figure which shows a conventional structure, and is a figure corresponding to FIG. It is a figure which shows a conventional structure, and is an enlarged view which expanded the upper part vicinity of FIG. 11A. It is a figure which shows a conventional structure, and is an enlarged view which expanded the lower part vicinity of FIG. 11A. It is a graph which shows in-plane distribution of the fastening force of a pair of flanges in a conventional structure.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic view showing a part of an exhaust system 1 of an engine as an internal combustion engine according to an embodiment of the present invention and a fastening structure 2 for exhaust system parts.

FIG. 1 shows a turbocharger turbine housing 10 as a first exhaust system component and a catalyst case 20 as a second exhaust system component. The turbine housing 10 includes a first flange 11, and the catalyst case 20 includes a second flange 21, and the first flange 11 and the second flange 21 include a pair of flanges 11, 21. Constitute.
The pair of flanges 11 and 21 are fastened and fastened in the radial direction by a coupling 30 as a fastening member.

FIG. 2 is a diagram showing a coupling 30 used in the present embodiment.
The coupling 30 has a structure in which the ends of a plurality of arcuate members connected so as to be swingable are connected by bolts, and includes a first arcuate member 31, a second arcuate member 32, And a third arcuate member 33. In addition, the coupling 30 includes a swing connecting portion 34 that connects the first arc-shaped member 31 and the second arc-shaped member 32 so as to be swingable, and the second arc-shaped member 32 and the third arc-shaped member. And a coupling force generating portion 36 for coupling the first arc-shaped member 31 and the third arc-shaped member 33 using a bolt 39.

  The swing connecting portions 34 and 35 are made of a thin plate metal having elasticity, and have a structure that swings when the thin plate portion is bent.

  The fastening force generating portion 36 includes a first connecting flange portion 37 provided at an end portion of the first arcuate member 31 and a second connecting flange portion provided at an end portion of the third arcuate member. 38 and a bolt 39 for connecting the first and second connecting flange portions 37, 38. The first connecting flange portion 37 is provided with a female screw portion for screwing the bolt 39.

  FIG. 3 is a diagram showing an LL cross section of FIG. 1, and is a schematic diagram showing an exhaust system component fastening structure 2 for fastening a pair of flanges 11, 21 in the exhaust system component by a coupling 30. .

  As shown in FIG. 3, a coupling 30 is provided on the outer periphery of the pair of flanges 11 and 21 (in FIG. 3, the flange 11 can be confirmed), and by tightening a bolt 39 of the coupling 30. The pair of flanges 11 and 21 are tightened in the radial direction.

FIG. 4A is a diagram schematically showing a cross section of M-O-N in FIG. 3.
As shown in FIG. 4A, the pair of flanges 11 and 21 are arranged with their end faces facing each other, and a coupling 30 is provided on the outer periphery thereof. A seal member (not shown) is disposed between the pair of flanges 11 and 21, and in a state where the pair of flanges 11 and 21 are fastened, there is a slight gap between the end surfaces of the pair of flanges 11 and 21. There is a gap.
As described above, by tightening the bolt 39 of the coupling 30, the pair of flanges 11 and 21 are tightened in the radial direction. As a result, the flange inclined surfaces of the pair of flanges 11 and 21 are pushed by the fastening inclined surface provided on the inner surface of the coupling 30 and facing the flange inclined surface, so that the pair of flanges 11 and 21 approach each other. Power works. By such an action, the pair of flanges 11 and 21 are fastened.

FIG. 5 is an enlarged view of the vicinity of the lower side of FIG. In the present embodiment, the overall flange angle θ defined by the first flange inclined surface 12 of the first flange 11 and the second flange inclined surface 22 of the second flange 21, that is, the first flange. The total flange angle θ, which is the sum of the first flange angle θ1 of 11 and the second flange angle θ2 of the second flange 21, is not constant over the entire circumference of the flange.
Specifically, as shown in FIG. 5, when the direction in which the fastening force generation point 36 is positioned is 180 ° with respect to the center of the pair of flanges 11, 21, a predetermined value within a range of ± 90 °. Is set to be larger than the overall flange angle θ in the other ranges.
Note that the dotted lines in FIG. 5 indicate the shapes of the first and second flanges 11 and 21 in the MO cross section of FIG. 3, for example.
As shown in FIG. 5, the first and second flange angles θ1 and θ2 mean angles formed between the end surface of the flange and the inclined surface of the flange.

  Next, the reason why the overall flange angle θ in the predetermined portion within the range of ± 90 ° is set larger than the overall flange angle θ in the other ranges will be described.

  10 and 11 are views showing a conventional structure in which a pair of flanges 11 and 21 are fastened using the coupling 30. FIG. FIG. 10 is a diagram showing a conventional structure corresponding to FIG. 3 of the present embodiment. FIG. 11 is a diagram showing a conventional structure corresponding to FIG. 4 of the present embodiment.

  As shown in FIGS. 10 and 11, in the conventional structure, the first flange 11 has the first flange inclined surface 12 and the second flange 21 has the second flange inclined surface 22 defined by the overall flange. The flange angle θ, that is, the total flange angle θ, which is the sum of the first flange angle θ1 of the first flange 11 and the second flange angle θ2 of the second flange 21, is constant over the entire circumference of the flange. Further, the coupling inclined surface angle φ of the coupling inner surface defined by the first fastening inclined surface 40 and the second fastening inclined surface 41 on the inner surface of the coupling 30 is also constant over the entire inner surface of the coupling 30. The overall flange angle θ and the fastening inclined surface angle φ are substantially the same angle.

  And in such a conventional structure, when the structure which fastens the perimeter of a flange by fastening one bolt 39, the fastening part of the bolt 39, ie, the fastening force generation | occurrence | production part 36 (part of 180 degrees) ) Around the pair of flanges 11 and 21 is strongly pressed by the coupling 30 and, as a result, a strong fastening force works. On the other hand, around the portion farthest from the fastening force generation point 36 (0 ° portion), the force with which the pair of flanges 11 and 21 are pressed becomes relatively weak, and the fastening force becomes weak.

  FIG. 12 is a graph showing the relationship between the fastening torque of the bolt 39 and the in-plane distribution of the fastening force between the pair of flanges 11 and 12 in the conventional structure. Here, the fastening force between the pair of flanges 11 and 12 means a force in a direction in which the flanges press against each other in a fastening surface where the pair of flanges 11 and 21 face each other, that is, a compression force.

  As shown in FIG. 12, in the conventional structure, the fastening force at the point B (0 ° portion) farthest from the fastening force generation location is that of the point A that is in the vicinity of the fastening force generation location (180 ° portion). The value is considerably lower than the fastening force. The fastening force at points C and D (90 ° and −90 ° portions) is a value between the fastening force at point A and the fastening force at point B. That is, in the conventional structure, since the contact state of the coupling with the pair of flanges is non-uniform, the in-plane distribution of the fastening force between the pair of flanges is also non-uniform.

  Therefore, in the conventional structure, in order to obtain a sufficient fastening force over the entire fastening surface of the flange, that is, in order to obtain a strong fastening force even at the point B, it is necessary to apply a very strong fastening torque to the bolt 39. .

In the present embodiment, the fastening inclined surface angle φ is constant over the entire circumference of the flange. 4 and 5, the overall flange angle θ defined by the first flange inclined surface 12 of the first flange 11 and the second flange inclined surface 22 of the second flange 21, That is, the sum θ of the first flange angle θ1 of the first flange 11 and the second flange angle θ2 of the second flange 21 is not constant over the entire circumference of the flange.
Specifically, with the center of the pair of flanges 11 and 21 as a reference, when the direction in which the fastening force generation point 36 is located is 180 °, the total flange angle θ in a predetermined portion within a range of ± 90 ° is In other ranges, it is set larger than the total flange angle θ.

  As described above, the overall flange angle θ in a predetermined portion within the range of ± 90 ° is set to be larger than the overall flange angle θ in the other range. The pair of flanges 11 and 21 are strongly pressed by the coupling 30 even in a part far from the force generation point (a predetermined part within a range of ± 90 °), and the contact state of the coupling with the pair of flanges 11 and 21 is improved. In addition, the in-plane distribution of the fastening force of the pair of flanges 11 and 21 is equalized. That is, even if the fastening structure employs a structure in which the entire circumference of the flange is fastened by fastening one bolt 39, the in-plane distribution of the fastening force between the flanges can be improved. .

  It should be noted that the effects of the present invention can be obtained even if the first flange angle θ1 and the second flange angle θ2 are not the same angle in a predetermined portion within the range of ± 90 °. However, it is preferable that the first flange angle θ1 and the second flange angle θ2 are substantially equal. In this case, at the time of fastening, the coupling can be pressed against the pair of flanges 11 and 21 with good balance.

In addition, it is preferable to provide a positioning unit (not shown) for positioning the relative rotational positions of the coupling 30 and the pair of flanges 11 and 21. For example, the positioning portion includes a concave portion provided in the coupling 30 and a convex portion provided in each of the pair of flanges 11 and 21, and the rotational position is determined by the engagement of the concave portion and the convex portion. Is done.
With such a structure, the relative position between the 180 ° position where the fastening force generation point 36 of the coupling 30 is disposed and the ± 90 ° range where the overall flange angle θ is set to be large is the opposite side. The rotational positional relationship is always properly positioned.
The convex portion may be provided not on the flange itself but on each of the exhaust system parts including the pair of flanges 11 and 21. Of course, a convex part may be provided on the coupling 30 side and a concave part may be provided on the flange side.

  In the present embodiment, the overall flange angle θ is set large within the range of ± 60 ° shown in FIG.

FIG. 6 is a graph showing the fastening force between the pair of flanges 11 and 21, that is, the flange fastening load, when the overall flange angle θ in the range of ± 60 ° is changed. The fastening inclined surface angle φ is constant over the entire circumference of the coupling 30. The fastening torque applied to the bolt 39 is constant.
The difference angle α is used on the horizontal axis of the graph. This is because the first fastening inclined surface 40 and the second fastening inclined surface of the fastening member are determined from the overall flange angle θ defined by the angle formed by the first flange inclined surface 12 and the second flange inclined surface 22. It is calculated by subtracting the fastening inclined surface angle φ defined by the angle formed by 41.

As shown in this graph, the larger the difference angle α in the aforementioned ± 60 ° range, that is, the greater the overall flange angle θ, the farthest from the fastening force generation point 36 and the lowest fastening load. At point B, which is the position, the load tends to increase.
Therefore, as the difference angle α in the range of ± 60 ° is increased, the contact state of the coupling with the pair of flanges 11 and 21 is improved, and the in-plane distribution of the fastening force between the pair of flanges 11 and 21 is uniform. The overall fastening force will also increase.

FIG. 7 is a diagram showing a modification of the present embodiment, and corresponds to FIG. In this modification, the overall flange angle θ is substantially constant over the entire circumference of the flange. On the other hand, the fastening inclined surface angle φ of the coupling inner surface defined by the first fastening inclined surface 40 and the second fastening inclined surface 41 on the inner surface of the coupling 30 is constant over the entire inner surface of the coupling 30. It is not.
Specifically, as shown in FIG. 7, when the direction in which the fastening force generation point 36 is positioned is 180 ° with respect to the center of the pair of flanges 11 and 21, a predetermined range within ± 90 ° is obtained. The fastening inclined surface angle φ in this part is set smaller than the fastening inclined surface angle φ in other ranges.
7 indicates the shapes of the first fastening inclined surface 40 and the second fastening inclined surface 41 on the inner surface of the coupling 30 in the MO cross section of FIG. 3, for example.

  As described above, when the fastening inclined surface angle φ in a predetermined portion within the range of ± 90 ° is set smaller than the fastening inclined surface angle φ in the other range, when one bolt 39 is tightened. The pair of flanges 11 and 21 are strongly pressed by the coupling 30 even in a portion far from the fastening force generation location (predetermined portion within a range of ± 90 °), and the coupling contact state with the pair of flanges 11 and 21 Is improved, and the distribution of the fastening force in the fastening surface between the pair of flanges 11 and 21 is equalized.

Note that, in a predetermined portion within a range of ± 90 °, a mode in which the overall flange angle θ is set large and a mode in which the fastening inclined surface angle φ is made small may be combined.
That is, the first fastening inclined surface 40 and the second fastening inclined surface 41 of the fastening member are determined from the overall flange angle θ defined by the angle formed by the first flange inclined surface 12 and the second flange inclined surface 22. When the angle obtained by subtracting the fastening inclined surface angle φ defined by the angle formed by the difference angle α is the center of the first and second flanges 11 and 21, the fastening force generation point 36 The effect of the present invention can be obtained if the difference angle α in the predetermined portion within the range of ± 90 ° when the position direction is 180 ° is larger than the difference angle α in the other ranges.
As described above, the section in which the overall flange angle θ is set to be large or the section in which the fastening inclined surface angle φ is set to be small is provided within a range of ± 90 °. The pair of flanges 11 and 21 are strongly pressed by the ring. Therefore, the contact state of the coupling with the pair of flanges 11 and 21 is improved, and the in-plane distribution of the fastening force between the pair of flanges 11 and 21 is equalized, and the effect of the present invention is obtained.

The section in which the overall flange angle θ is set to be large or the section in which the fastening inclined surface angle φ is set to be small is preferably a range wider than ± 45 ° and narrower than ± 75 °. More preferably, the range is ± 60 °. By setting to such a range, the in-plane distribution of the fastening force between the pair of flanges 11 and 21 can be more effectively equalized.
In addition, when using a coupling provided with three circular-arc-shaped members 31, 32, and 33 as shown in FIG. 2, the circular arc-shaped part far from the fastening force generation point 36 among the three circular-arc-shaped members. The effect of the present invention can be obtained by setting the fastening inclined surface angle φ of the inner peripheral surface of the member 32 to be smaller than the fastening inclined surface angle φ of the inner peripheral surfaces of the other arc-shaped members 31 and 33. In this case, since the fastening inclined surface angle φ has only to be set for each member of the arcuate member, the fastening structure of the present invention can be easily configured.
In particular, when using a coupling having three arc-shaped members 31, 32, 33, the fastening inclined surface angle φ in the above-described ± 60 ° range can be easily set small. With this configuration, it is possible to equalize the distribution of the fastening force in the fastening surface between the pair of flanges very effectively, and the overall fastening force is also improved.

In addition, as a coupling, not only the coupling 30 shown by FIG. 2 but various couplings are employable.
For example, a coupling 60 including three swinging portions 65, 66, and 67 as shown in FIG. 8 and including four arcuate members 61, 62, 63, and 64 may be employed.
In this case, in the coupling 60, the fastening inclined surface angle φ of the inner surfaces of the arc-shaped members 62 and 63 far from the fastening force generation point 36 is set as the fastening inclined surface of the inner peripheral surface of the other arc-shaped members 31 and 33. The effect of the present invention can be obtained by setting the angle smaller than the angle φ.

Thus, when using a coupling comprising arcuate members as outer periphery fastening members at three or more locations as couplings as fastening members, at least one location provided within the aforementioned ± 90 ° range. It is preferable to set the fastening inclined surface angle φ of the inner peripheral surface of the arc-shaped member small. In this case, since the fastening inclined surface angle φ can be set for each member of the arcuate member, the fastening structure of the present invention can be easily configured.
For example, in the case of using a coupling including 4 to 5 arcuate members, the fastening inclined surface angle φ of the inner peripheral surface of the 1 to 2 arcuate members far from the fastening force generation site is set small.
Moreover, when using a coupling provided with 6-7 circular arc-shaped members, fastening inclination-surface angle (phi) of the internal peripheral surface of 1-3 arc-shaped members far from a fastening force generation location is set small.

When the number of the arc-shaped members is an even number, it is preferable to set the fastening inclined surface angle φ of the inner peripheral surfaces of the two arc-shaped members far from the fastening force generation location 36 to be small. Thereby, a pair of flanges 11 and 21 can be tightened appropriately with good balance.
The outer periphery tightening member is usually an arc-shaped member. However, for example, when the number of outer periphery tightening members is large, the outer periphery tightening member does not necessarily have an arc shape.

Moreover, as a coupling, the coupling 70 provided with the one rocking | fluctuation connection part 73 as shown in FIG. 9, and the two circular-arc-shaped members 71 and 72 may be employ | adopted. The swing connecting portion 73 of the coupling 70 includes a first folded portion 75 provided on one end side of the first arcuate member 71 and a second end provided on one end side of the second arcuate member 72. The folded portion 76 is constituted by an annular member 77 that connects the first and second folded portions 75 and 76. Further, the fastening force generation portion 74 includes a bolt 78 and a nut 79, and the fastening force is generated by screwing the bolt 78 into the nut 79.
Even when such a coupling is used, by setting the fastening inclined surface angle φ in a predetermined portion within the above-described ± 90 ° range to be smaller than the fastening inclined surface angle φ in other ranges, 1 When the bolts 39 are tightened, the pair of flanges 11 and 21 are strongly pressed by the coupling 30 even at a portion far from the portion where the fastening force is generated (a predetermined portion within a range of ± 90 °). The contact state of the coupling with the flanges 11 and 21 is improved, and the in-plane distribution of the fastening force between the pair of flanges 11 and 21 is equalized.
For example, with respect to the fastening inclined surface angle φ of the inner surfaces of the first arc-shaped member 71 and the second arc-shaped member 72, a portion close to the fastening force generation location 36 is set large, and the fastening force generation location 36 moves away. Accordingly, the angle φ may be continuously changed to be small. Of course, it is good also as an aspect which changes discontinuously.

  The exhaust system component fastening structure according to the present embodiment has the following effects.

(1) In the exhaust system component fastening structure according to the present embodiment, the first flange 30 of the coupling 30 is determined from the overall flange angle θ defined by the angle formed by the first flange inclined surface 12 and the second flange inclined surface 22. When the angle obtained by subtracting the fastening inclined surface angle φ defined by the angle formed by the fastening inclined surface 40 and the second fastening inclined surface 42 is a difference angle α, the first and second flanges 11, When the direction in which the fastening force generation point 36 is located is 180 ° with the center of 21 as a reference, the difference angle α in a predetermined portion within a range of ± 90 ° is larger than the difference angle α in other ranges. .
Therefore, the contact state of the fastening member with respect to the first and second flanges can be improved, and as a result, the in-plane distribution of the fastening force between the first and second flanges can be improved.

(2) In the exhaust system component fastening structure according to the present embodiment, the overall flange angle θ in a predetermined portion within the range of ± 90 ° is set larger than the overall flange angle θ in other ranges.
Therefore, the contact state of the coupling 30 with respect to the first and second flanges 11 and 21 can be improved by devising the shape of the flange. As a result, the fastening force between the first and second flanges 11 and 21 can be improved. The in-plane distribution of can be improved.

(3) In the exhaust system component fastening structure according to the present embodiment, the first flange angle θ1 and the second flange angle θ2 in a predetermined portion within the range of ± 90 ° are substantially equal.
Therefore, at the time of fastening, the coupling 30 can be pressed against the first and second flanges 11 and 21 with a good balance.

  (4) Since the exhaust system component fastening structure according to the present embodiment further includes a positioning portion for positioning the rotational position of the coupling 30 and the first and second flanges 11 and 21, the coupling The relative rotational positional relationship between the above-mentioned 180 ° position where 30 fastening force generation points 36 are arranged and the above-described ± 90 ° range where the overall flange angle θ is set large is Always properly positioned.

(5) In the exhaust system component fastening structure according to the present embodiment, the fastening slope angle φ at a predetermined portion within the range of ± 90 ° is set smaller than the fastening slope angle φ at other ranges. .
Therefore, the contact state of the coupling 30 with respect to the first and second flanges 11 and 21 can be improved by devising the shape of the coupling 30, and as a result, the first and second flanges 11 and 21 can be connected to each other. The in-plane distribution of the fastening force can be improved.

(6) In the exhaust system component fastening structure according to the present embodiment, the coupling 30 includes three or more arc-shaped members, and one or more arc-shaped members provided within the range of ± 90 ° described above. The fastening inclined surface angle φ is set smaller than the fastening inclined surface angle φ of the other arcuate members.
Therefore, since the fastening inclined surface angle φ can be set for each member of the arcuate member, the fastening structure of the present invention can be easily configured.

(7) In the exhaust system component fastening structure according to the present embodiment, the direction in which the predetermined portion described above is located at the fastening force generation location 36 is 180 ° with respect to the centers of the first and second flanges 11 and 21. In this case, it is provided in a range wider than ± 45 ° and narrower than ± 75 °.
Therefore, the in-plane distribution of the fastening force between the first and second flanges 11 and 21 can be equalized more effectively.

In this embodiment, the exhaust system component fastening structure of the internal combustion engine has been described. However, this fastening structure is not limited to the internal combustion engine, and can be applied to various exhaust system parts fastening structures.
Note that the present invention is not limited to the above-described embodiment, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Exhaust system of engine (internal combustion engine) 2 ... Fastening structure of exhaust system parts 10 ... Turbine housing of supercharger (first exhaust system parts)
DESCRIPTION OF SYMBOLS 11 ... 1st flange 12 ... 1st flange inclined surface 20 ... Catalyst case (2nd exhaust system component)
21 ... 2nd flange 22 ... 2nd flange inclined surface 30, 60, 70 ... Coupling (fastening member)
31, 32, 33... Arc-shaped member (outer periphery fastening member)
36 ... Fastening force generation point 40 ... First fastening inclined surface 41 ... Second fastening inclined surface 61, 62, 63, 64 ... Arc-shaped member (outer periphery fastening member)

Claims (7)

A first flange provided on the first exhaust system component and having a first flange inclined surface;
A second flange provided on a second exhaust system component different from the first exhaust system component and having a second flange inclined surface;
A fastening force generating portion, a first fastening inclined surface that faces the first flange inclined surface at the time of fastening, and a second fastening inclined surface that faces the second flange inclined surface at the time of fastening; An exhaust system component fastening structure comprising: a fastening member that fastens and fastens the first and second flanges in the radial direction by the first and second fastening inclined surfaces according to the force generated at the fastening force generation location. Because
An angle formed by the first fastening inclined surface and the second fastening inclined surface of the fastening member from an overall flange angle defined by an angle formed by the first flange inclined surface and the second flange inclined surface. When the angle obtained by subtracting the fastening inclined surface angle defined by
The difference angle at a predetermined portion within a range of ± 90 ° when the direction in which the fastening force generation point is located is 180 ° with respect to the centers of the first and second flanges is in another range. An exhaust system component fastening structure that is larger than the differential angle.   The difference angle in the predetermined portion within the range of ± 90 ° is obtained by setting the total flange angle in the predetermined portion within the range of ± 90 ° larger than the total flange angle in the other range. The exhaust system component fastening structure according to claim 1, wherein is larger than the difference angle in other ranges. An angle formed between the first flange inclined surface and the flange end surface of the first flange is defined as a first flange angle, and an angle formed between the second flange inclined surface and the flange end surface of the second flange is defined as a first angle. When the flange angle is 2,
The overall flange angle is defined by the sum of the first flange angle and the second flange angle;
The exhaust system component fastening structure according to claim 2, wherein the first flange angle and the second flange angle at a predetermined portion within the range of ± 90 ° are substantially equal.   The exhaust system component fastening structure according to any one of claims 2 to 3, further comprising a positioning portion for positioning rotational positions of the fastening member and the first and second flanges.   The fastening inclined surface angle in the predetermined portion within the range of ± 90 ° is set to be smaller than the fastening inclined surface angle in the other range, so that the predetermined portion in the range of ± 90 ° The exhaust system component fastening structure according to claim 1, wherein the difference angle is larger than the difference angle in other ranges. The fastening member comprises three or more outer peripheral fastening members disposed on the outer periphery of the first and second flanges,
The said fastening inclination angle of the one or more outer periphery fastening members provided in the range of the said +/- 90 degrees is set smaller than the fastening inclination angle of other outer periphery fastening members. Exhaust system parts fastening structure.   The predetermined portion is a range wider than ± 45 ° when the direction in which the fastening force is generated is 180 ° with respect to the centers of the first and second flanges, and ± 75 The exhaust system component fastening structure according to any one of claims 1 to 6, wherein the exhaust system component fastening structure is provided in a range narrower than °.

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