JP2011021573A - Turbocharger - Google Patents

Abstract

A turbocharger in which an inner housing is further disposed in a turbine housing so as to surround a turbine wheel, and the turbine housing is attached to the inner housing. Suppress.
A plurality of exhaust inlets 15 extending in a circumferential direction of a rotor shaft 6 are formed in the inner housing 11 with a support column 16 interposed therebetween. The inner housing 11 and the bearing housing 4 are assembled by tightening bolts 21 via spacers 20 into bolt holes formed in a plurality along the circumferential direction of the flange 13 formed on the outer peripheral portion of the inner housing 11. The spacer 20 is located between one of the portions of the flange 13 corresponding to the column 16 adjacent in the circumferential direction of the rotor shaft 6 in the column 16 and is arcuate along the circumferential direction of the rotor shaft 6. It is arranged so as to extend.
[Selection] Figure 1

Description

  The present invention relates to a turbocharger for an internal combustion engine.

  Conventionally, an internal combustion engine is equipped with a turbocharger for the purpose of forcibly sending intake air into a combustion chamber to increase its charging efficiency. The turbocharger includes a turbine housing that is provided in the middle of the exhaust passage and accommodates the turbine wheel, a compressor housing that is provided in the middle of the intake passage and accommodates the compressor wheel, and a rotor that connects the turbine wheel and the compressor wheel. And a shaft. When the turbine wheel is rotated by blowing exhaust gas, the compressor wheel is rotated together with the rotor shaft along with this rotation, and the intake of the intake passage is forcibly sent to the combustion chamber by the rotation of the compressor wheel.

  Incidentally, an exhaust gas purification catalyst for purifying exhaust gas is provided downstream of the turbocharger in the exhaust passage, and the exhaust gas exhausted from the turbine housing is purified by the exhaust gas purification catalyst and then released into the atmosphere. The Further, the exhaust purification catalyst can efficiently purify the exhaust gas when the temperature is within a predetermined temperature range, that is, within the temperature range where the catalyst is activated. However, when the temperature of the turbine housing is low, such as during a cold start, the heat of the exhaust is absorbed by the turbine housing, resulting in a decrease in the temperature of the exhaust. In such a case, the temperature rise of the exhaust purification catalyst is delayed, and it becomes difficult to efficiently purify the exhaust gas with the exhaust purification catalyst. Accordingly, a turbocharger having a turbine housing that suppresses a decrease in the temperature of the exhaust by reducing the thickness of the turbine housing and suppressing the heat of the exhaust from being absorbed by the turbine housing has been proposed and put into practical use. Has reached the point.

  However, since the turbine housing having a small thickness has low rigidity, the turbine housing may be deformed by high-temperature exhaust flowing during operation of the internal combustion engine. Therefore, for the purpose of ensuring the strength of the turbine housing and suppressing the deformation, an inner housing is further provided in the turbine housing so as to surround the turbine wheel, and the turbine housing is attached to the inner housing. A turbocharger has been proposed (see, for example, Patent Document 1).

  Hereinafter, a turbocharger provided with such an inner housing will be described with reference to FIGS. First, the shape of the inner housing 11 will be described with reference to FIG. As shown in FIG. 5, the inner housing 11 includes a cylindrical portion 12 extending along the axis C of the rotor shaft 6 (see FIG. 7), a covered cylindrical connecting portion 17 connected to the cylindrical portion 12, and And a flange 13 extending outward from the end of the connecting portion 17.

  6 is a cross-sectional view showing a cross section taken along the line AA of FIG. As shown in FIG. 5 and FIG. 6, the exhaust port 15 is formed in the connecting portion 17 so as to open in the radial direction at equal angular intervals in the circumferential direction. These exhaust inlets 15 are formed in the shape of a long hole extending in the circumferential direction at the connecting portion 17 as shown in FIG. Further, struts 16 extending along the axis C of the rotor shaft 6 are formed between the exhaust introduction ports 15. 5 and 6, the flange 13 is formed with a plurality of bolt holes 13a at predetermined intervals in the circumferential direction.

  Next, a cross-sectional structure of a turbocharger in which such an inner housing 11 is disposed will be described with reference to FIG. As shown in FIG. 7, the turbine housing 2 is fixed to the flange 13 and the cylindrical portion 12 of the inner housing 11. A scroll passage 3 through which exhaust gas introduced from the exhaust passage flows is formed by a space defined by the inner housing 11 and the turbine housing 2. The exhaust gas flowing through the scroll passage 3 is guided to the inside through the exhaust gas inlet 15 and blown to the turbine wheel 1. Thereby, the turbine wheel 1 comes to rotate.

  On the other hand, the turbine housing 2 is attached to the bearing housing 4 by attaching the bearing housing 4 that accommodates the rotor shaft 6 to the inner housing 11. FIG. 8 is a cross-sectional view showing a cross section taken along line BB in FIG. As shown in FIGS. 7 and 8, bolts 21 are screwed into the respective bolt holes 13 a formed in the flange 13 through spacers 20. The spacer 20 has a bolt hole 20d through which the bolt 21 is inserted. The inner housing 11 is assembled to the bearing housing 4 together with the turbine housing 2 by tightening these bolts 21 and pinching the outer periphery of the bearing housing 4 with the spacer 20 and the flange 13. As shown in FIG. 8, the turbine housing 2 is connected to an exhaust manifold 32 and is fixed to an internal combustion engine (not shown) by a fixing member 31.

JP 2008-121470 A

  By the way, in the inner housing 11, the vicinity of the exhaust introduction port 15 has lower rigidity in the direction orthogonal to the rotor shaft 6 than that of the support column 16. Further, the exhaust inlet 15 is easily deformed due to thermal expansion because high-temperature exhaust flows. For this reason, if the vicinity of the exhaust inlet 15 in the inner housing 11 is deformed and expanded, the turbine housing 2 may be deformed accordingly.

  When the turbine housing 2 and the inner housing 11 are deformed in this way, the shape of the scroll passage 3 changes to reduce the supercharging performance, or exhaust leakage occurs at the fastening portion between the inner housing 11 and the bearing housing 4. Resulting in. This exhaust leak can cause a local high temperature and, in turn, can cause cracks in this area.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a turbocharger in which an inner housing is disposed so as to surround a turbine wheel in the turbine housing, and the turbine housing is attached to the inner housing. It is to increase the rigidity and suppress the deformation of the exhaust due to the heat.

In the following, means for achieving the above object and its effects are described.
According to the first aspect of the present invention, a turbine housing that houses a turbine wheel that rotates about a rotor shaft as a rotation axis, and is positioned in the turbine housing and attached to the turbine housing to form a scroll passage together with the turbine housing. An inner housing and a bearing housing that pivotally supports the rotor shaft, and the inner housing has an opening extending in a circumferential direction of the rotor shaft and guides exhaust gas from the scroll passage toward the turbine wheel. An exhaust flange is formed along the circumferential direction of the rotor shaft with the support column interposed therebetween, and an annular flange that is fitted around the outer peripheral portion of the bearing housing is formed, and a plurality of flanges are formed along the circumferential direction of the flange. Through the spacer to the bolt hole to be formed In the turbocharger in which the inner housing is assembled to the bearing housing together with the turbine housing by screwing a bolt, tightening the bolt, and pinching the outer periphery of the bearing housing by the spacer and the flange. The pillars are positioned between one of the flanges corresponding to the pillars adjacent to each other in the circumferential direction of the rotor shaft, and extend in an arc shape along the circumferential direction of the rotor shaft. And at least both ends thereof include spacers on which the bolts are respectively disposed.

  According to this configuration, the spacer is formed between one of the support columns adjacent to each other in the circumferential direction of the rotor shaft among the flanges of the inner housing, that is, sandwiched between the support columns to form an exhaust inlet. It comes to be arrange | positioned corresponding to a site | part. By the way, the part corresponding to the exhaust inlet of the flange has a lower rigidity in the direction orthogonal to the rotor shaft than the part corresponding to the support column. However, when these spacers are disposed at the portion corresponding to the exhaust introduction port by being tightened by the bolts as described above, the rigidity of the portion corresponding to the exhaust introduction port in the direction is increased. For this reason, in the turbocharger in which the inner housing is further disposed in the turbine housing so as to surround the turbine wheel, and the turbine housing is attached to the inner housing, the rigidity of the turbocharger can be increased. The deformation due to the heat of the exhaust gas can be suppressed.

  According to a second aspect of the present invention, the turbine housing has an exhaust inflow portion connected to an exhaust manifold and is attached to an internal combustion engine via a fixing member, and the fixing member has an axis of the rotor shaft. The gist of the invention is that the turbine housing is fixed to the turbine housing at a position facing the exhaust inflow portion.

  When the portion where the turbine housing is connected to the exhaust manifold and the portion attached to the fixed member are positioned so as to face each other across the axis of the rotor shaft, if these are expanded by the heat of the exhaust, these members The turbine housing may be deformed into an elliptical shape. In this regard, according to the same configuration, the spacer is disposed to increase the rigidity in the direction perpendicular to the rotor shaft of the turbine housing, and as a result, such deformation of the turbine housing can be suppressed.

  According to a third aspect of the present invention, the spacer has an arc shape extending in both directions of the flow direction of the exhaust gas in the scroll passage and the opposite direction from the exhaust inflow portion formed in the turbine housing, and at least at both ends thereof. The gist further includes spacers on which the bolts are respectively disposed.

  A part of the exhaust gas introduced from the exhaust manifold into the turbine housing stays in an exhaust inflow portion that is a connection portion between the turbine housing and the exhaust manifold. For this reason, the site | part centering on this exhaust inflow part tends to become high temperature rather than another site | part with the heat | fever of exhaust_gas | exhaustion. And the site | part which becomes high temperature in this way becomes a thing which deform | transforms easily with the heat. In this respect, according to the same configuration, the spacer is disposed so as to extend in both directions of the exhaust flow direction and the opposite direction from the exhaust inflow portion. Can be high. Therefore, thermal deformation of the turbine housing at this part can be suppressed.

  According to a fourth aspect of the present invention, a turbine housing that houses a turbine wheel that rotates about a rotor shaft as a rotation axis, and is positioned in the turbine housing and attached to the turbine housing to form a scroll passage together with the turbine housing. An inner housing and a bearing housing that pivotally supports the rotor shaft, wherein the inner housing is formed with a plurality of exhaust introduction ports that guide exhaust from the scroll passage toward the turbine wheel, and an outer periphery of the bearing housing An annular flange that is externally fitted to the part is formed, a bolt is screwed into a plurality of bolt holes formed along the circumferential direction of the flange via a spacer, and the bolt is tightened to secure the outer peripheral part of the bearing housing. The spacer and the flange Therefore, in the turbocharger in which the inner housing is assembled to the bearing housing together with the turbine housing by pinching, the spacer is formed in the turbine housing and connected to an exhaust manifold from an exhaust inflow portion, and exhaust gas in the scroll passage is formed. An arc-shaped first spacer extending in the flow direction, and an arc-shaped second spacer disposed at a position facing the first spacer across the axis of the rotor shaft. The gist of the spacer and the second spacer is that the bolts are disposed at least at both ends thereof.

  The part extending along the flow direction of the exhaust gas in the scroll passage from the exhaust inflow portion becomes higher in temperature than the other parts due to the heat of the exhaust gas introduced by the exhaust manifold. And the site | part which becomes high temperature in this way becomes a thing which is easy to thermally deform. In this regard, according to the same configuration, the first spacer is disposed so as to extend from the exhaust inflow portion in the flow direction of the exhaust gas in the scroll passage, so that the rigidity of this portion in the direction can be increased. become. Therefore, in the turbocharger in which the inner housing is further disposed in the turbine housing so as to surround the turbine wheel, and the turbine housing is attached to the inner housing, the rigidity of the turbocharger can be increased. The deformation due to the heat of the exhaust can be suppressed.

  As a specific example of the spacer arrangement method, the fixing position by the fixing member is sandwiched between the end portions of the first spacer and the second spacer in the circumferential direction of the rotor shaft. It is possible to adopt a configuration in which these spacers are arranged as described above. Further, as a specific example of the shape of the spacer, as in the invention described in claim 6, a configuration in which the first spacer has a semicircular arc shape can be adopted.

  According to a seventh aspect of the present invention, a turbine housing that houses a turbine wheel that rotates about a rotor shaft as a rotation shaft, and is positioned in the turbine housing and attached to the turbine housing to form a scroll passage together with the turbine housing. An inner housing and a bearing housing that pivotally supports the rotor shaft, wherein the inner housing is formed with a plurality of exhaust introduction ports that guide exhaust from the scroll passage toward the turbine wheel, and an outer periphery of the bearing housing An annular flange that is externally fitted to the part is formed, a bolt is screwed into a plurality of bolt holes formed along the circumferential direction of the flange via a spacer, and the bolt is tightened to secure the outer peripheral part of the bearing housing. The spacer and the flange Therefore, in the turbocharger in which the inner housing is assembled to the bearing housing together with the turbine housing by pinching, the exhaust inflow portion of the turbine housing is connected to the exhaust manifold and is attached to the internal combustion engine via a fixing member. The fixing member is fixed to the turbine housing at a fixed position facing the exhaust inflow portion across the axis of the rotor shaft, and the spacer is an imaginary connecting the exhaust inflow portion and the fixed position. The first and second spacers are spaced apart from each other on both sides of the wire and extend in the circumferential direction of the flange and serve as a common spacer for a plurality of bolts. Rigidity of the part connecting the part where the bolt is inserted , And summarized in that is set lower than the rigidity of the portion the bolt is inserted.

  When the first spacer and the second spacer are disposed so as to sandwich an imaginary line connecting the exhaust inflow portion and the fixed position, when the inner housing expands due to the heat of exhaust, the turbine housing is Deforms to bend around a line. If the turbine housing is deformed in this way, stress may concentrate on the portion of the inner housing corresponding to the central portion of the spacer and the inner housing may be damaged. In this regard, according to the same configuration, these spacers are set so that the rigidity of the parts connecting the parts through which the bolts are inserted is set lower than the rigidity of the parts through which these bolts are inserted. In this case, a portion connecting the portion through which the bolt is inserted is deformed. For this reason, even if it is a case where an inner housing expand | swells, it becomes possible to suppress a deformation | transformation of the inner housing corresponding to the center part of a spacer. Accordingly, in the turbocharger in which the inner housing is further disposed in the turbine housing so as to surround the turbine wheel, and the turbine housing is attached to the inner housing, the rigidity of the turbocharger can be increased. The deformation due to the heat of the exhaust can be suppressed.

1 is a cross-sectional view of a turbocharger according to a first embodiment. Sectional drawing of the turbocharger concerning 2nd Embodiment. Sectional drawing of the turbocharger concerning 3rd Embodiment. Sectional drawing of the turbocharger concerning other embodiment. The perspective view of the conventional inner housing. Sectional drawing of the conventional inner housing. Sectional drawing of the conventional turbocharger. Sectional drawing which shows the cross section along the BB line of FIG.

(First embodiment)
A first embodiment of a turbocharger according to the present invention will be described below with reference to FIG. The present invention is characterized by the shape and arrangement of the spacer for fastening the inner housing to the bearing housing together with the turbine housing. The shape of the inner housing (excluding bolt hole formation positions), the turbine Since the internal structure of the housing and the bearing housing are the same as those of the conventional turbocharger shown in FIGS.

  FIG. 1 shows a cross-sectional structure along a direction orthogonal to the rotor shaft 6 for the turbocharger according to the present embodiment. As shown in FIG. 1, an exhaust inflow portion 33 communicating with the exhaust manifold 32 is formed in the upper portion of the turbine housing 2. An exhaust passage (not shown) is formed in the exhaust manifold 32, and the exhaust discharged from the internal combustion engine is discharged into the exhaust passage and then the scroll passage 3 (FIG. 7) through the exhaust inflow portion 33. To be introduced).

  On the other hand, a fixing member 31 that supports the turbine housing 2 is attached at a position facing the exhaust inflow portion 33 across the axis of the rotor shaft 6. The other end of the fixing member 31 is fixed to the internal combustion engine, whereby the turbine housing 2 is fixed to the internal combustion engine.

  In the turbine housing 2, an inner housing 11 in which a column portion 16 and an exhaust introduction port 15 are formed is disposed. In the inner housing 11, as shown in FIG. 1, the two struts 16 are located in a part close to the exhaust inflow part 33, and one strut part is located in a part close to the fixing member 31. It is arranged.

  A plurality of bolt holes 13a are formed at equal angular intervals along the circumferential direction of the annular flange 13 formed on the outer peripheral portion of the inner housing 11, and the bolt holes 13a include spacers. Bolts 21 are respectively screwed through 20. Further, bolt holes (not shown) through which the bolts 21 are inserted are formed at both ends of the spacers 20 corresponding to the positions where the bolt holes of the flange 13 are formed. Then, by tightening the bolt 21, the outer peripheral portion of the bearing housing 4 is pinched by the spacer 20 and the flange 13. Thus, the flange 13 of the inner housing 11 is assembled to the bearing housing 4 together with the turbine housing 2.

  The spacer 20 is located between one of the portions of the flange 13 corresponding to each of the adjacent column portions 16 and extends from the other to extend in an arc shape along the circumferential direction of the rotor shaft 6. . In the present embodiment, the support columns 16 are formed at four positions so as to be equiangularly spaced in the circumferential direction of the inner housing 11, and the spacers 20 are respectively adjacent to the adjacent support columns 16 and the flanges 13 corresponding thereto. One piece is disposed between one part and the other part.

  Further, these spacers 20 are fastened to the flange 13 and the bearing housing 4 by inserting bolts 21 at both ends. As described above, the exhaust introduction port 15 is formed in the inner housing 11 so as to sandwich the support column portion 16. For this reason, when the spacers 20 are disposed between one of the portions of the flanges 13 corresponding to the column portions 16 adjacent to each other along the circumferential direction of the rotor shaft 6, the spacers 20 are arranged. Is disposed at each part of the flange 13 corresponding to each of the exhaust inlets 15.

  Thus, since the spacer 20 is fastened to the flange 13 and the bearing housing 4 by the bolt 21, the portion where the spacer 20 is disposed in the circumferential direction of the flange 13 is more than the portion where the spacer 20 is not disposed. The rigidity in the direction orthogonal to the shaft 6 is increased.

According to the embodiment described above, the following effects can be obtained.
(1) Among the flanges 13 of the inner housing 11, the spacer 20 is sandwiched between one of the column portions 16 adjacent to each other in the circumferential direction of the rotor shaft 6, that is, between the column portions 16, and the exhaust introduction port 15. Is arranged corresponding to the site where the is formed. Here, a portion of the flange 13 corresponding to the exhaust inlet 15 has a lower rigidity in a direction perpendicular to the rotor shaft 6 than a portion corresponding to the support column 16. However, since these spacers 20 are disposed by being fastened by the bolts 21 as described above at the portion corresponding to the exhaust inlet 15, the portion of the flange 13 adjacent to the exhaust inlet 15 with respect to the direction. Stiffness is increased. For this reason, in the turbocharger in which the inner housing 11 is further disposed in the turbine housing 2 so as to surround the turbine wheel 1 and the turbine housing 2 is attached to the inner housing 11, the rigidity thereof can be increased. As a result, deformation of the exhaust due to the heat of the exhaust can be suppressed. Further, by suppressing such deformation, it is possible to suitably suppress exhaust leakage at the fastening portion between the inner housing 11 and the bearing housing 4.

(2) A portion where the turbine housing 2 is connected to the exhaust manifold 32 and a portion attached to the fixing member 31 are positioned so as to face each other across the axis of the rotor shaft 6. For this reason, when the inner housing 11 expands due to the heat of the exhaust, it is pressed by these members, and the turbine housing 2 may be deformed into an elliptical shape as indicated by a two-dot chain line in FIG. According to the present embodiment, as a result of the spacer 20 being disposed, the rigidity of the turbine housing 2 in the direction orthogonal to the rotor shaft 6 is increased, so that such deformation of the inner housing 11 and the turbine housing 2 is suppressed. Will be able to.
(Second Embodiment)
Next, a turbocharger according to a second embodiment of the present invention will be described with reference to FIG. In addition, the same number is attached | subjected to the member equivalent to 1st Embodiment, and the description is omitted.

  FIG. 2 shows a cross-sectional structure along the direction orthogonal to the rotor shaft 6 for the turbocharger according to the present embodiment. As shown in FIG. 2, in the circumferential direction of the flange 13, a portion corresponding to the flow direction of the exhaust from the exhaust inflow portion 33 (see the arrow direction in FIG. 2) in the scroll passage 3 (see FIG. 7) has a semicircular arc shape. The first spacer 20a is disposed. Bolt holes (not shown) through which the bolts 21 are inserted are formed in the first spacer 20a so as to correspond to the positions where the bolt holes 13a of the flange 13 are formed, including both ends thereof. Further, a quarter-arc-shaped second spacer 20b is disposed at a portion facing the first spacer 20a across the axis of the rotor shaft 6. Bolt holes (not shown) through which the bolts 21 are inserted are formed at both ends of the second spacer 20b so as to correspond to the positions where the bolt holes of the flange 13 are formed. Then, by tightening the bolt 21 through these bolt holes, the outer peripheral portion of the bearing housing 4 is pinched by the spacer 20 and the flange 13. Further, in the circumferential direction of the flange 13, a fixing member 31 is disposed at a position sandwiched between the end portions of the first spacer 20a and the second spacer 20b.

  Since the exhaust gas introduced from the exhaust inflow portion 33 is cooled while flowing through the scroll passage 3, its temperature is highest in the exhaust inflow portion 33 and decreases as it flows through the scroll passage 3. Accordingly, the part corresponding to the flow direction of the exhaust from the exhaust inflow portion 33 is likely to be hotter than the other parts. And in the site | part which becomes high temperature in this way, the inner housing 11 becomes a thing which carries out a heat deformation easily.

  Therefore, in the present embodiment, the first spacer 20a is disposed so as to extend in an arc shape in the flow direction of the exhaust gas from the exhaust gas inflow portion 33 in the scroll passage 3, so that the inner housing 11 corresponding to this portion is arranged. The rigidity in the direction orthogonal to the rotor shaft 6 is increased. Thereby, the deformation | transformation of the turbine housing 2 resulting from the thermal deformation of the inner housing 11 in this part can be suppressed now. In addition, since the first spacer 20a is formed in a semicircular arc shape extending long in the circumferential direction of the flange 13, a single spacer is disposed corresponding to such a high temperature portion. The deformation of the housing 2 can be suitably suppressed.

According to the embodiment described above, the following effects can be obtained.
(3) The portion extending from the exhaust inflow portion 33 along the flow direction of the exhaust gas in the scroll passage 3 becomes hotter than the other portions due to the heat of the exhaust gas introduced by the exhaust manifold 32 and is likely to be thermally deformed. . According to the present embodiment, since the first spacer 20a is disposed so as to extend from the exhaust inflow portion 33 in the flow direction of the exhaust gas in the scroll passage 3, the rigidity of this portion can be increased. . Therefore, in the turbocharger in which the inner housing 11 is disposed so as to further surround the turbine wheel 1 in the turbine housing 2 and the turbine housing 2 is attached to the inner housing 11, the rigidity thereof can be increased. Thus, it is possible to suppress the deformation of the exhaust due to the heat. Further, by suppressing such deformation, it is possible to suitably suppress exhaust leakage at the fastening portion between the inner housing 11 and the bearing housing 4.
(Third embodiment)
Next, a turbocharger according to a third embodiment of the present invention will be described with reference to FIG. In addition, the same number is attached | subjected to the member equivalent to 1st Embodiment, and the description is omitted.

  FIG. 3 shows a cross-sectional structure in a direction perpendicular to the rotor shaft 6 for the turbocharger according to the present embodiment. As shown in FIG. 3, in this embodiment, a first spacer 20 a and a second spacer 20 b each having a semicircular arc shape extending in the circumferential direction of the flange 13 of the inner housing 11 are disposed. The first spacer 20a and the second spacer 20b are spaced apart from each other with a virtual line D connecting the exhaust manifold 32 and the fixing member 31 therebetween, and are arranged so as to be symmetrical with respect to the virtual line D. Yes.

  Each of the first spacer 20a and the second spacer 20b has three bolt holes (not shown) through which the bolts 21 are inserted so as to correspond to the formation positions of the bolt holes 13a of the flange 13 including both ends thereof. Is formed. The three bolts 21 are inserted into positions at equal angular intervals in the circumferential direction of the bolt holes formed in the flange 13. Of the first spacer 20a and the second spacer 20b, the portion through which the bolt 21 is inserted (A in FIG. 3) is more than the portion connecting the portion through which the bolt 21 is inserted (B in FIG. 3). The area when viewed from the axial direction of the rotor shaft 6 is increased. For this reason, the part into which the bolt 21 is inserted has higher bending rigidity than the part connecting the part through which the bolt 21 is inserted.

According to the embodiment described above, the following effects can be obtained.
(4) Since the first spacer 20a and the second spacer 20b are disposed so as to sandwich the virtual line D connecting the exhaust inflow portion 33 and the fixing member 31, the inner housing 11 expands due to the heat of the exhaust. Then, the turbine housing 2 is deformed so as to be bent with the imaginary line D as an axis. If the turbine housing 2 is deformed in this manner, stress may concentrate on the portion of the inner housing 11 corresponding to the central portion of the first spacer 20a and the second spacer 20b, and the inner housing 11 may be damaged. According to the present embodiment, the first spacer 20a and the second spacer 20b are set such that the rigidity of the part connecting the part through which the bolt 21 is inserted is lower than the rigidity of the part through which the bolt 21 is inserted. Therefore, when the inner housing 11 is deformed, a portion connecting the portion through which the bolt 21 is inserted is deformed. For this reason, even if the inner housing 11 is expanded, the deformation of the inner housing 11 corresponding to the central portions of the first spacer 20a and the second spacer 20b can be suppressed. Therefore, in the turbocharger in which the inner housing 11 is disposed so as to further surround the turbine wheel 1 in the turbine housing 2 and the turbine housing 2 is attached to the inner housing 11, the rigidity of the turbocharger can be increased. Thus, it is possible to suppress the deformation of the exhaust due to the heat. Further, by suppressing such deformation, it is possible to suitably suppress exhaust leakage at the fastening portion between the inner housing 11 and the bearing housing 4.

  Furthermore, in the first spacer 20a and the second spacer 20b, the area when the part connecting the part through which the bolt 21 is inserted is viewed from the axial direction of the rotor shaft 6 rather than the part through which the bolt 21 is inserted. Since it is formed to be small, the amount of heat input from the turbine housing 2 to the bearing housing 4 through the first spacer 20a and the second spacer 20b can be reduced. For this reason, the thermal stress of the bearing housing 4 can be reduced.

In addition, embodiment described above can be implemented in the aspect which changed the form suitably as follows.
In the first embodiment, the four spacers 20 are disposed, but the present invention is not limited to this. For example, as shown in FIG. 4, it may further include an arcuate spacer 20 extending from the exhaust inflow portion 33 formed in the turbine housing 2 in both directions of the flow direction of the exhaust gas in the scroll passage 3 and the opposite direction. . In other words, the semicircular arc spacer 20 may be disposed so that the exhaust inflow portion 33 is at the center. Part of the exhaust gas introduced from the exhaust manifold 32 into the turbine housing 2 stays in the vicinity of the exhaust inflow portion 33, which is a connection portion between the turbine housing 2 and the exhaust manifold 32. For this reason, the site | part centering on this exhaust inflow part 33 tends to become high temperature rather than another site | part with the heat | fever of exhaust_gas | exhaustion. And the site | part which becomes high temperature in this way becomes a thing which deform | transforms easily with the heat. In this regard, according to the present embodiment, the spacer 20 is disposed so as to extend from the exhaust inflow portion 33 in both directions of the flow direction of the exhaust gas and in the opposite direction. The rigidity in the direction can be increased. Therefore, deformation of the turbine housing 2 due to thermal deformation of the inner housing 11 at this portion can be suppressed.

  -In 1st Embodiment, although the support | pillar part 16 was formed in four places, this invention is not limited to this. For example, the three support columns 16 are formed at three positions so as to be equiangularly spaced from each other, and the three columns are positioned between one of the portions of the flange 13 corresponding to each of the adjacent support columns 16 and the other. A spacer 20 may be provided. Also in this embodiment, the effect according to the said effect can be show | played.

  In the third embodiment, in the first spacer 20a and the second spacer 20b, the portion where the bolt 21 is inserted is more axial than the portion where the portion where the bolt 21 is inserted is connected in the axial direction. However, the present invention is not limited to this. For example, the material of the part through which the bolt 21 is inserted is different from the material of the part connecting the part through which the bolt 21 is inserted, and the rigidity of the part connecting the part through which the bolt 21 is inserted is It can also be made lower than the rigidity of the portion to be inserted. Also in this embodiment, the effect according to said (4) can be show | played.

  In the above embodiment, the exhaust inflow portion 33 and the fixing member 31 are positioned so as to face each other with the axis of the rotor shaft 6 interposed therebetween, but the present invention is not limited to this. Even if the mounting position of the fixing member 31 is changed, the operational effects according to the above (1), (3), and (4) can be obtained.

  DESCRIPTION OF SYMBOLS 1 ... Turbine wheel, 2 ... Turbine housing, 3 ... Scroll path, 4 ... Bearing housing, 6 ... Rotor shaft, 11 ... Inner housing, 12 ... Cylindrical part, 13 ... Flange, 13a ... Bolt hole, 15 ... Exhaust inlet, DESCRIPTION OF SYMBOLS 16 ... Column part, 17 ... Connection part, 20 ... Spacer, 20a ... 1st spacer, 20b ... 2nd spacer, 20d ... Bolt hole, 21 ... Bolt, 31 ... Fixing member, 32 ... Exhaust manifold, 33 ... Exhaust Inflow part.

Claims (7)

A turbine housing that houses a turbine wheel that rotates with a rotor shaft as a rotation axis, an inner housing that is located in the turbine housing and is attached to the turbine housing and defines a scroll passage together with the turbine housing, and the rotor shaft as a shaft And a bearing housing that supports the inner shaft. The inner housing has an opening extending in a circumferential direction of the rotor shaft, and a plurality of exhaust introduction ports for guiding exhaust from the scroll passage toward the turbine wheel sandwich the support column. An annular flange formed along the circumferential direction of the rotor shaft and fitted around the outer periphery of the bearing housing is formed, and a plurality of bolt holes formed along the circumferential direction of the flange are provided with spacers. Screw the bolt and In the turbocharger inner housing is assembled to the bearing housing together with the turbine housing by clamping 掴 by said spacer and said flange of the outer peripheral portion of the bearing housing tightened,
The spacer is located between one of the portions of the flange corresponding to each column portion adjacent in the circumferential direction of the rotor shaft among the column portions and is arcuate along the circumferential direction of the rotor shaft. A turbocharger including spacers disposed at least at both ends thereof, wherein the bolts are respectively disposed. The turbine housing has an exhaust inflow portion connected to an exhaust manifold and is attached to the internal combustion engine via a fixing member, and the fixing member faces the exhaust inflow portion with an axis of the rotor shaft interposed therebetween. The turbocharger according to claim 1, wherein the turbocharger is fixed to the turbine housing at a position. The spacer has an arc shape extending from an exhaust inflow portion formed in the turbine housing in both directions of the exhaust flow in the scroll passage and in the opposite direction, and the bolts are disposed at least at both ends thereof. The turbocharger according to claim 1, further comprising a spacer. A turbine housing that houses a turbine wheel that rotates with a rotor shaft as a rotation axis, an inner housing that is located in the turbine housing and is attached to the turbine housing and defines a scroll passage together with the turbine housing, and the rotor shaft as a shaft A plurality of exhaust inlets for guiding exhaust from the scroll passage toward the turbine wheel, and an annular flange that is externally fitted to the outer periphery of the bearing housing. And a bolt is screwed into a plurality of bolt holes formed along the circumferential direction of the flange via a spacer, and the bolt is tightened to clamp the outer periphery of the bearing housing by the spacer and the flange. By In a turbocharger the inner housing is assembled to the bearing housing together with the turbine housing,
The spacer is formed in the turbine housing and connected to an exhaust manifold, and an arc-shaped first spacer extending in an exhaust flow direction in the scroll passage and an axis of the rotor shaft sandwiching the first spacer. An arc-shaped second spacer disposed at a position opposite to the first spacer, and the bolts are disposed at least at both ends of the first spacer and the second spacer, respectively. Turbocharger. The turbine housing is attached to the internal combustion engine via a fixing member, and the fixing member is fixed to the turbine housing at a position facing the exhaust inflow portion with the shaft center of the rotor shaft interposed therebetween. 5. The turbo according to claim 4, wherein the first spacer and the second spacer are disposed so that their positions are sandwiched between the end portions of the first spacer and the second spacer in the circumferential direction of the rotor shaft. Charger. The turbocharger according to claim 4, wherein the first spacer has a semicircular arc shape. A turbine housing that houses a turbine wheel that rotates with a rotor shaft as a rotation axis, an inner housing that is located in the turbine housing and is attached to the turbine housing and defines a scroll passage together with the turbine housing, and the rotor shaft as a shaft A plurality of exhaust inlets for guiding exhaust from the scroll passage toward the turbine wheel, and an annular flange that is externally fitted to the outer periphery of the bearing housing. And a bolt is screwed into a plurality of bolt holes formed along the circumferential direction of the flange via a spacer, and the bolt is tightened to clamp the outer periphery of the bearing housing by the spacer and the flange. By In a turbocharger the inner housing is assembled to the bearing housing together with the turbine housing,
The turbine housing has an exhaust inflow portion connected to an exhaust manifold and is attached to the internal combustion engine via a fixing member, and the fixing member faces the exhaust inflow portion with an axis of the rotor shaft interposed therebetween. Fixed to the turbine housing in a fixed position;
The spacers are arranged on both sides of the imaginary line connecting the exhaust inflow portion and the fixed position so as to be spaced apart from each other, extend in the circumferential direction of the flange, and serve as a common spacer for a plurality of bolts. The first and second spacers are characterized in that the rigidity of the part connecting the part through which the bolt is inserted is set lower than the rigidity of the part through which the bolt is inserted. Turbocharger.

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