JP6683750B2 - Flange fastening structure - Google Patents

Description

  According to the present invention, a first flange that surrounds an outlet opening of a first exhaust passage member and a second flange that surrounds an inlet opening of a second exhaust passage member are brought into contact with each other to form a first flange and a second flange. The present invention relates to a flange coupling structure that integrally couples a first exhaust passage member and a second exhaust passage member by fastening a fitting fastening ring with a fastening member.

  The flange provided at the outlet opening of the turbocharger and the flange provided at the inlet opening of the catalytic converter are butted against each other, and a ring-shaped fastening member is fitted to the outer circumferences of both flanges and fastened with a bolt, whereby the turbocharger and the The one in which a catalytic converter is integrally connected is known from Patent Document 1 below.

JP 2005-344580 A

  By the way, in the above-mentioned conventional one, since the coupling surface of the flange on the turbocharger side and the coupling surface of the flange on the catalytic converter side are simply butted against each other, it is not possible to perform mutual positioning in the circumferential direction. When the flange is fastened with the fastening member, the assembling phase of the turbocharger and the catalytic converter may vary.

  In addition, the turbocharger flange and the catalytic converter flange have dimensional errors during manufacturing, and both flanges are exposed to exhaust gas and thermally expand to different dimensions. As a result, the surface pressure of the joint surface when being fastened by the fastening member becomes unstable, which may cause the exhaust gas to leak.

  The present invention has been made in view of the above circumstances, and improves the accuracy of the assembly phase of the fastening portions of the flanges of the turbocharger and the exhaust passage member, and prevents the leakage of exhaust gas from the joint surface of both flanges with a simple structure. The purpose is to do.

In order to achieve the above object, according to the invention described in claim 1, the first coupling surface of the annular first flange provided so as to surround the outlet opening of the first exhaust passage member, and the second The circumference of the fastening ring that is in contact with the second coupling surface of the annular second flange that is provided so as to surround the inlet opening of the exhaust passage member and that fits on the outer circumferences of the first flange and the second flange. The first exhaust passage member and the second exhaust passage member are compressed by circumferentially and axially compressing the first flange and the second flange by fastening the divided portions formed at one position in the direction with a fastening member. And a locking piece provided on one of the first connecting surface and the second connecting surface to be locked in a locking hole provided on the other, and And the phase with respect to the locking hole 180 DEG position, one one of the first flange and the second flange to have a fitting projection and the other have a fitting recess in which the fitting convex portion is fitted, the fitting projection The portion and the fitting concave portion are provided inside the outer edge portion in the radial direction of the first coupling surface and the second coupling surface, and the fitting convex portion and the fitting concave portion are in surface contact with each other, and in the said second flange and the first flange, the direction of the first flange is made of a material having a large coefficient of thermal expansion, the fastening of the flange the fitting convex portion, characterized in Rukoto provided in the first flange A structure is proposed .

Na us, corresponds to the first exhaust passage member of the turbocharger 11 according to the present invention of the embodiment corresponds to the second exhaust passage member of the catalytic converter 12 is the invention of the embodiment, the positioning hole 14c of the embodiment Corresponds to the locking hole of the present invention, the positioning pin 16c of the embodiment corresponds to the locking piece of the present invention, and the bolt 19 of the embodiment corresponds to the fastening member of the present invention.

  According to the configuration of claim 1, the first coupling surface of the annular first flange provided so as to surround the outlet opening of the first exhaust passage member and the inlet opening of the second exhaust passage member are surrounded. The divided member formed at one circumferential position of the fastening ring, which is in contact with the second coupling surface of the provided annular second flange and is fitted to the outer circumferences of the first flange and the second flange, is a fastening member. By fastening, the first flange and the second flange are compressed in the circumferential direction and the axial direction to integrally connect the first exhaust passage member and the second exhaust passage member.

  At a position where the locking piece provided on one of the first coupling surface and the second coupling surface is locked in the locking hole provided on the other, and the phase is shifted by about 180 ° with respect to the locking piece and the locking hole. Since one of the first flange and the second flange has a fitting protrusion and the other has a fitting recess into which the fitting protrusion fits, the locking piece and the locking hole lock the first exhaust gas. Not only the assembly phase of the passage member and the second exhaust passage member automatically becomes constant, but also the radial displacement due to thermal expansion and dimensional error of both flanges due to the fitting convex part and the mating concave part mating. By the straightening, the surface pressures of the first and second coupling surfaces of both the flanges when they are fastened by the fastening ring are made uniform in the circumferential direction, and the leakage of exhaust gas is prevented.

Also, the fitting projection and the fitting recess is disposed inside the outer edge portion in the first coupling surface and a second coupling surface radial, since the fitting projection and the fitting depression in surface contact with each other As compared with the case where the fitting recess is open to the outer edge of the first flange or the second flange, the correction force for the radial displacement due to thermal expansion and dimensional error of both flanges is increased, and the leakage of exhaust gas is further enhanced. Certainly prevented.

Furthermore , between the first flange and the second flange, the first flange is made of a material having a higher coefficient of thermal expansion, and the fitting protrusion is provided on the first flange. By pressing the fitting convex portion against the fitting concave portion due to the difference in the amount of thermal expansion, the radial displacement of both flanges is corrected more effectively .

FIG. 5 is a perspective view of a turbocharger and a catalytic converter coupled in the V band. (First embodiment) FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. 1 (sectional view taken along line 2-2 of FIG. 3). (First embodiment) FIG. 3 is a sectional view taken along line 3-3 of FIG. 2. (First embodiment) It is operation explanatory drawing at the time of flange fastening by V band. (First embodiment) It is an operation explanatory view at the time of flange fastening by V band (comparative example). It is a figure which shows the shape of a fitting convex part and a fitting concave part. (Second embodiment) It is a figure which shows the shape of a fitting convex part and a fitting concave part. ( Reference form)

First embodiment

  The first embodiment of the present invention will be described below with reference to FIGS.

  As shown in FIG. 1, the turbocharger 11 is connected downstream of the exhaust manifold of the engine, and the catalytic converter 12 is connected downstream of the turbocharger 11. The turbocharger 11 drives the turbine with the exhaust gas of the engine and supplies the air compressed by the compressor connected to the turbine to the intake system of the engine to improve the output of the engine. The catalytic converter 12 purifies harmful substances such as hydrocarbons, carbon monoxide, and nitrogen oxides contained in the exhaust gas of the engine with a catalyst using platinum, palladium, rhodium, or the like. The catalytic converter 12 is arranged immediately downstream of the turbocharger 11 where the temperature of the exhaust gas is high, because the purification performance of harmful substances increases as the exhaust gas supplied to the catalytic converter 12 has a higher temperature.

  The outer shell of the turbocharger 11 is made of a material having a large thermal expansion coefficient (for example, austenite type), and the outer shell of the catalytic converter 12 is made of a material having a small thermal expansion coefficient (for example, ferrite type).

  As shown in FIGS. 2 and 3, the outlet opening 13a of the casing 13 of the turbocharger 11 having a circular cross section is provided with an annular first flange 14 that tapers radially outward. The first flange 14 includes a first coupling surface 14a that is orthogonal to the axis of the casing 13, and a first tapered surface 14b that tapers radially outward with respect to the first coupling surface 14a. On the other hand, an annular second flange 16 that tapers radially outward is provided at the inlet opening 15a of the circular cross section of the casing 15 of the catalytic converter 12. The second flange 16 includes a second coupling surface 16a that is orthogonal to the axis of the casing 15 and a second tapered surface 16b that tapers radially outward with respect to the second coupling surface 16a.

  The first flange 14 of the turbocharger 11 and the second flange 16 of the catalytic converter 12 are integrally connected by a connecting means called a V band 17. The fastening ring 18 that constitutes the main body of the V-band 17 is an annular member that is cut off at one place on the circumference, and its cross section has a first tapered surface 18a, a second tapered surface 18b, and an outer peripheral surface 18c. It is V-shaped with and. Arm portions 18d and 18d are respectively provided on the pair of separated ends of the fastening ring 18 so as to project outward in the radial direction, and the first taper surface 18a is provided at a position shifted in phase by 180 ° with respect to both arm portions 18d and 18d. And the hinge part 18e which notches the 2nd taper surface 16b and leaves only the outer peripheral surface 18c is formed. The fastening ring 18 can be opened and closed by elastically deforming the hinge portion 18e so that the both arm portions 18d, 18d approach and separate from each other, and a bolt 19 penetrating the both arm portions 18d, 18d is screwed into the nut 20. It can be tightened to reduce the diameter.

  The second coupling surface 16a of the second flange 16 is provided with a positioning pin 16c having a circular cross section, and the first coupling surface 14a of the first flange 14 is provided with a positioning hole 14c into which the positioning pin 16c can fit without a gap. To be done. Further, a rectangular parallelepiped fitting protrusion 24 is formed on the first coupling surface 14a of the first flange 14, and the fitting protrusion 24 is fitted on the second coupling surface 16a of the second flange 16 without a gap. A possible fitting recess 25 is formed.

  The positioning pin 16c and the positioning hole 14c are provided at a radial intermediate position between the second flange 16 and the first flange 14, and the fitting convex portion 24 and the fitting concave portion 25 have the diameter of the first flange 14 and the second flange 16, respectively. It is provided at an intermediate position in the direction. Further, the phases of the fitting convex portion 24 and the fitting concave portion 25 are shifted by 180 ° from the phases of the positioning pin 16c and the positioning hole 14c. That is, the positioning pin 16c and the positioning hole 14c are located at one end side on one diameter line passing through the centers of the first flange 14 and the second flange 16, and the fitting projection 24 and the fitting recess 25 are located at the other end. is doing.

  As is apparent from FIG. 4, in order to connect the turbocharger 11 and the catalytic converter 12, the first connecting surface 14 a of the first flange 14 of the turbocharger 11 and the second connecting surface of the second flange 16 of the catalytic converter 12 are connected. The fastening ring 18 of the V-band 17 is fitted to the outer circumferences of the first flange 14 and the second flange 16 in a state where they are abutted against each other with the gasket 21 in between. When the bolt 19 is screwed into the nut 20 and tightened in this state, the first taper surface 14b of the first flange 14 pushed by the first taper surface 18a of the fastening ring 18 moving inward in the radial direction and the inner side in the radial direction. And the second tapered surface 18b of the second flange 16 pressed by the second tapered surface 18b of the fastening ring 18 move toward each other, and the first coupling surface 14a of the first flange 14 and the second tapered surface 18b of the second flange 16 move toward each other. The turbocharger 11 and the catalytic converter 12 are integrally coupled by fastening the second coupling surface 16a of the flange 16 with the gasket 21 interposed therebetween.

  By the way, when the first flange 14 of the turbocharger 11 and the second flange 16 of the catalytic converter 12 are coupled with each other by the V band 17, the catalytic converter 12 is coupled with the phase shifted from the phase of the turbocharger 11. If this happens, the position of the outlet of the catalytic converter 12 and the position of the exhaust pipe connected thereto will shift, and there is a risk that the work of assembling the exhaust pipe to the catalytic converter 12 will be hindered.

  However, according to the present embodiment, when the first flange 14 of the turbocharger 11 and the second flange 16 of the catalytic converter 12 are connected by the V band 17, they are provided on the second connecting surface 16a of the second flange 16. By fitting the positioning pin 16c into the positioning hole 14c provided in the first flange 14, the phases of the turbocharger 11 and the catalytic converter 12 are automatically regulated, so that the turbocharger 11 and the catalytic converter 12 are fixed at a fixed position. They can be linked by relationships (see Figure 4).

  Since there is a manufacturing error in the dimension of the first flange 14 of the turbocharger 11 and the dimension of the second flange 16 of the catalytic converter 12, the outer diameter of the first flange 14 and the outer diameter of the second flange 16 are different from each other. It does not always match. Moreover, not only is there a temperature difference between the first flange 14 of the turbocharger 11 located upstream in the flow direction of the exhaust gas and the second flange 16 of the catalytic converter 12 located downstream, As shown in FIG. 2, since the waste gate 22 and the turbine outlet portion 23 are disposed inside the turbocharger 11 at positions eccentric from the center of the first flange 14, the waste gate 22 and the turbine are disposed on the first flange 14. A temperature difference in the circumferential direction occurs depending on the distance from the outlet 23.

  As described above, since it is inevitable that the first flange 14 and the second flange 16 have a dimensional difference due to manufacturing or a dimensional difference due to thermal expansion, the first flange 14 and the second flange 16 are tentatively fitted to each other. Assuming that the convex portion 24 and the fitting concave portion 25 are not provided, when the first flange 14 and the second flange 16 are positioned by the positioning pin 16c and the positioning hole 14c, as shown in FIG. The radial outer ends of the first flange 14 and the second flange 16 may be displaced by the distance α at a position where the phase is shifted by 180 ° from. When the first flange 14 and the second flange 16 are fastened with the V band 17 in this state, the fastening ring 18 of the V band 17 is inclined and the surface pressures of the first and second coupling surfaces 14a and 16a become unstable. Exhaust gas may leak from.

  However, according to the present embodiment, the fitting convex portion 24 and the fitting concave portion 25 are fitted to each other at the position where the phase is shifted by 180 ° from the positioning pin 16c and the positioning hole 14c. Since the outer ends in the radial direction are corrected so as to be aligned, when fastening the first flange 14 and the second flange 16 with the V band 17, the fastening ring 18 of the V band 17 is prevented from tilting, and the first, It is possible to stabilize the surface pressure of the second coupling surfaces 14a and 16a and prevent the exhaust gas from leaking (see FIG. 3).

  Further, as shown in FIG. 5B, the fitting convex portion 24 and the fitting concave portion 25 are provided on the outer side in the radial direction of the first flange 14 and the second flange 16, and the fitting concave portion 25 is the second flange. When it is opened to the outer peripheral surface of 16, the fitting convex portion 24 projects radially outward from the fitting concave portion 25, and the fitting convex portion 24 and the fitting concave portion 25 form the first flange 14 and the second flange 16. The position correction function of may not be exhibited. The same applies to the case where the fitting convex portion 24 and the fitting concave portion 25 are provided inside the first flange 14 and the second flange 16 in the radial direction.

  However, according to the present embodiment, since the fitting convex portion 24 and the fitting concave portion 25 are provided in the radial middle portion of the first flange 14 and the second flange 16, the fitting convex portion 24 is fitted. It does not project radially outward or radially inward from the concave portion 25, and the function of correcting the position of the first flange 14 and the second flange 16 by the fitting convex portion 24 and the fitting concave portion 25 is effectively exerted.

  As described above, according to the present embodiment, the positioning pin 16c provided on the second flange 16 and the positioning hole 14c provided on the first flange 14 are fitted to each other, so that the turbocharger 11 and the catalytic converter 12 have the same structure. Not only the assembling phase automatically becomes constant, but also the fitting protrusion 24 provided on one of the first flange 14 and the second flange 16 at the position 180 ° out of phase with the positioning pin 16c and the positioning hole 14c. When it is fastened with the V-band 17, it is automatically fitted to the fitting recess 25 provided in the first flange 14 and the second flange 16 so as to automatically correct the radial displacement due to the dimensional error and the difference in thermal expansion. It is possible to prevent the exhaust gas from leaking by making the surface pressures of the first and second coupling surfaces of both flanges uniform in the circumferential direction.

Second embodiment

  Next, a second embodiment of the present invention will be described based on FIG.

  FIG. 6 shows the cross-sectional shapes of the first flange 14 and the second flange 16 at positions where the phases are shifted by 180 ° from the positioning pin 16c and the positioning hole 14c. The first flange 14 is provided with two fitting projections 24, 24 each having a triangular cross-section that inclines radially outward toward the second flange 16, and the second flange 16 includes the first flange 14 Two fitting concave portions 25, 25 having a triangular cross section are formed so that the fitting convex portions 24, 24 of are in surface contact without a gap.

  According to the present embodiment, when the first flange 14 having a large coefficient of thermal expansion tries to move radially outward relative to the second flange 16 having a small coefficient of thermal expansion, the fitting protrusions 24, 24 are fitted together. By closely contacting the recesses 25, 25 so as to bite into them, it is possible to effectively correct the radial displacement of the first flange 14 and the second flange 16.

Reference form

Next, a reference embodiment of the present invention will be described with reference to FIG.

  FIG. 7 shows the cross-sectional shapes of the first flange 14 and the second flange 16 at positions where the phases are shifted by 180 ° from the positioning pin 16c and the positioning hole 14c. In the first and second embodiments, the first flange 14 and the second flange 16 are provided with the fitting convex portion 24 and the fitting concave portion 25, respectively, but in the third embodiment, the first flange 14 is provided. The fitting recessed portion 25 is formed on the outer surface in the radial direction, and the fitting protruding portion 24 is provided on the inner surface in the radial direction of the second flange 16.

According to this reference embodiment, when the first flange 14 having a large coefficient of thermal expansion tries to move radially outward with respect to the second flange 16 having a small coefficient of thermal expansion, the fitting recess 25 moves from the radially inner side to the outer side. By closely contacting with the fitting convex portion 24, the positional deviation of the first flange 14 and the second flange 16 in the radial direction can be effectively corrected.

Although the embodiments and reference embodiments of the present invention have been described above, the present invention can be modified in various ways without departing from the scope of the invention.

  For example, the exhaust passage member of the present invention is not limited to the turbocharger 11 and the catalytic converter 12 of the embodiment, and may be any member such as an exhaust pipe through which exhaust gas passes.

  In the embodiment, the positioning pin 16c is provided on the second flange 16 side and the positioning hole 14c is provided on the first flange 14 side. However, the positional relationship is reversed, and the positioning pin is provided on the first flange 14 side. A positioning hole may be provided on the second flange 16 side.

  Further, the numbers of the fitting convex portions 24 and the fitting concave portions 25 are not limited to those in the embodiment, and can be set appropriately.

11 Turbocharger (first exhaust passage member)
12 Catalytic converter (second exhaust passage member)
13a Outlet opening 14 First flange 14a First coupling surface 14c Positioning hole (locking hole)
15a Entrance opening 16 Second flange 16a Second coupling surface 16c Positioning pin (locking piece)
18 Fastening ring 19 Bolt (fastening member)
24 Fitting convex part 25 Fitting concave part

Claims (1)

A first coupling surface (14a) of an annular first flange (14) provided so as to surround the outlet opening (13a) of the first exhaust passage member (11), and an inlet of the second exhaust passage member (12). The second coupling surface (16a) of the annular second flange (16) provided so as to surround the opening (15a) abuts each other, and the first flange (14) and the second flange (16). The first flange (14) and the second flange (16) can be formed by fastening a divided portion formed at one position in the circumferential direction of the fastening ring (18) fitted to the outer periphery of the first flange (14) and the second flange (16). A flange coupling structure for circumferentially and axially compressing to integrally couple the first exhaust passage member (11) and the second exhaust passage member (12),
The locking piece (16c) provided on one of the first coupling surface (14a) and the second coupling surface (16a) is locked in the locking hole (14c) provided on the other side, and the locking piece ( 16c) and the locking hole (14c) at a position shifted in phase by about 180 °, one of the first flange (14) and the second flange (16) has a fitting protrusion (24). to one and the other have a fitting recess (25) in which the fitting projection (24) is fitted,
The fitting protrusion (24) and the fitting recess (25) are provided inside the outer edge portion in the radial direction of the first coupling surface (14a) and the second coupling surface (16a), and The fitting convex portion (24) and the fitting concave portion (25) are in surface contact with each other,
In the first flange (14) and the second flange (16), the first flange (14) is made of a material having a higher coefficient of thermal expansion, and the fitting convex portion (24) has the first protrusion (24). fastening structure of the flange, characterized in Rukoto provided in the flange (14).

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