JP7327264B2 - turbine housing - Google Patents

Description

The present invention relates to turbine housings.

2. Description of the Related Art Conventionally, a double structure turbine housing is known as a turbine housing of a turbocharger. For example, a turbine housing as disclosed in Patent Document 1 is formed of an interior member and an exterior member that accommodates the interior member with a gap therebetween. The interior member forms at least an inner wall of a spiral scroll flow path that is a part of an exhaust passage through which exhaust gas discharged from the engine flows and surrounds the turbine wheel.

JP 2016-108974 A

By the way, the exhaust gas discharged from the engine contains water vapor. Here, the interior member is warmed by the heat of the exhaust gas, but since a gap is formed between the interior member and the exterior member, it is difficult to transfer heat from the interior member to the exterior member. . Therefore, there is a temperature difference between the exterior member and the interior member, and the temperature of the exterior member is lower than that of the interior member. At this time, for example, when the exhaust gas flows into the gap between the exterior member and the interior member, the exhaust gas is cooled by heat exchange between the exhaust gas flowing into the gap and the exterior member. Condensed water may occur in the gaps due to condensation of the water vapor contained in the If the condensed water generated in this way accumulates in the gap, it may cause corrosion of the exterior member and the interior member.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems, and an object thereof is to provide a turbine housing capable of suppressing accumulation of condensed water in a gap between an exterior member and an interior member. to do.

A turbine housing that solves the above problems includes an interior member that forms at least the inner wall of a spiral scroll flow passage that is a part of an exhaust passage through which exhaust gas discharged from an engine flows and that surrounds a turbine wheel. and an exterior member that accommodates the interior member with a gap therebetween, wherein the interior member has a communicating portion that communicates the cavity with the exhaust passage.

According to this, for example, the exhaust gas flows into the gap between the exterior member and the interior member, and the exhaust gas is cooled by heat exchange between the exhaust gas flowing into the gap and the exterior member. Even if water vapor contained in the exhaust gas is condensed and condensed water is generated in the gap, the condensed water can be discharged from the gap through the communicating portion to the exhaust passage. The condensed water discharged from the gap to the exhaust passage through the communicating portion flows through the exhaust passage together with the exhaust gas flowing through the exhaust passage or evaporates due to the heat of the exhaust gas. It is possible to prevent condensed water from accumulating in the gaps.

In the above-described turbine housing, the communicating portion may be formed in a portion of the interior member located vertically below an axis of the turbine wheel extending in the horizontal direction.

When condensed water is generated in the gap, the condensed water generated in the gap flows downward in the vertical direction through the gap due to its own weight. At this time, since the communication portion is formed in a portion of the interior member located vertically below the axis of the turbine wheel extending in the horizontal direction, the condensed water flows vertically downward through the gap due to its own weight. is easily discharged from the gap to the exhaust passage through the communicating portion. Therefore, the condensed water generated in the gap can be efficiently discharged from the gap to the exhaust passage via the communication part, and the accumulation of the condensed water in the gap can be easily suppressed.

In the above turbine housing, the exterior member includes a bottomed cylindrical housing main body portion having a plate-like bottom wall and a peripheral wall that is cylindrically erected from an outer peripheral portion of the bottom wall; and the housing main body portion. a closing member that closes the opening of the peripheral wall of the inner member, the interior member having a scroll passage forming plate that forms an inner wall of the scroll passage on the side of the housing main body, and the gap portion: A scroll gap formed between the housing main body and the scroll passage forming plate may be included, and the communication portion may include a scroll communication portion for communicating the scroll gap and the scroll passage.

Exhaust gas flows into the scroll gap formed between the housing main body and the scroll passage forming plate, and heat is exchanged between the exhaust gas flowing into the scroll gap and the housing main body, whereby the exhaust gas is released. As the exhaust gas is cooled, water vapor contained in the exhaust gas may be condensed to form condensed water in the gaps of the scroll. Even in this case, the condensed water can be discharged from the scroll gap through the scroll communicating portion to the scroll flow path. The condensed water discharged from the scroll gap to the scroll passage through the scroll communication portion flows through the scroll passage together with the exhaust gas flowing through the scroll passage or evaporates due to the heat of the exhaust gas. It is possible to prevent condensed water from accumulating in the scroll gap between the plate and the scroll passage forming plate.

In the turbine housing described above, the scroll communicating portion may be formed at the lowest portion of the scroll passage forming plate.
Since the condensed water generated in the scroll gap flows vertically downward through the scroll gap due to its own weight, the condensed water generated in the sucrose gap tends to accumulate at the bottom of the scroll gap. At this time, since the scroll communicating portion is formed at the lowest portion of the scroll passage forming plate, the condensed water accumulated in the lowest portion of the scroll gap portion is discharged from the scroll gap portion to the scroll passage via the scroll communicating portion. easy to be Therefore, the condensed water generated in the scroll gap can be efficiently discharged from the scroll gap through the scroll communication portion to the scroll flow path, and the accumulation of the condensed water in the scroll gap can be easily suppressed.

In the above turbine housing, the scroll clearance portion is a clearance reduction in which the distance between the inner peripheral surface of the housing body portion and the outer peripheral surface of the scroll passage forming plate gradually decreases as the distance between the inner peripheral surface of the housing body portion and the outer peripheral surface of the scroll passage forming plate approaches the scroll communication portion. It is good to have a part.

According to this, the volume of the part of the scroll gap part vertically below the scroll communicating part is smaller than that of the structure in which the scroll gap part does not have the gap reduction part. Therefore, the condensed water accumulated in the lowermost portion of the scroll gap is more easily discharged from the scroll gap through the scroll communicating portion to the scroll flow path. Therefore, the condensed water generated in the scroll gap can be more efficiently discharged from the scroll gap to the scroll flow path through the scroll communication part, and it is easier to suppress accumulation of the condensed water in the scroll gap. can.

In the above turbine housing, the interior member has a cylindrical introduction passage forming plate that forms an inner wall of an introduction passage that is a part of the exhaust passage and introduces the exhaust gas into the scroll passage. The exterior member has a cylindrical introduction portion forming portion that accommodates the introduction passage forming plate, and the gap portion is an introduction portion formed between the introduction portion forming portion and the introduction passage forming plate. A space may be included, and the communication portion may include an introduction portion communication portion that allows communication between the introduction portion space and the exhaust passage.

Exhaust gas flows into the introduction part gap formed between the introduction part forming part and the introduction channel forming plate, and heat exchange is performed between the exhaust gas flowing into the introduction part gap and the introduction part forming part. As a result, the exhaust gas is cooled, and the water vapor contained in the exhaust gas may be condensed to produce condensed water in the inlet space. Even in this case, the condensed water can be discharged from the inlet opening to the exhaust passage via the inlet communicating portion. Then, the condensed water discharged from the introduction part gap through the introduction part communication part into the exhaust passage flows through the exhaust passage together with the exhaust gas flowing through the exhaust passage or evaporates due to the heat of the exhaust gas. It is possible to prevent condensed water from accumulating in the introduction part gap between the plate and the introduction passage forming plate.

In the turbine housing described above, the introduction portion communication portion may be formed at the lowest portion of the introduction passage forming plate.
Since the condensed water generated in the introduction part gap flows vertically downward through the introduction part gap due to its own weight, the condensed water generated in the introduction part gap tends to accumulate at the lowest part of the introduction part gap. At this time, since the introduction portion communication portion is formed at the lowest portion of the introduction passage forming plate, the condensed water accumulated in the lowest portion of the introduction portion gap is exhausted from the introduction portion gap through the introduction portion communication portion. It is easy to be discharged into the aisle. Therefore, the condensed water generated in the introduction part gap can be efficiently discharged from the introduction part gap through the introduction part communication part to the exhaust passage, thereby suppressing the accumulation of the condensed water in the introduction part gap. It can be done easily.

In the above turbine housing, the interior member further includes an annular plate that forms an inner wall of the scroll passage on the side of the closing member, and the gap is formed between the closing member and the annular plate. An annular space may be included, and the communicating portion may include an annular plate communicating portion that communicates between the annular space and the scroll flow path.

Exhaust gas flows into an annular gap formed between the closing member and the annular plate, and heat is exchanged between the exhaust gas flowing into the annular gap and the closing member to cool the exhaust gas. Water vapor contained therein may condense to form condensed water in the annular space. Even in this case, the condensed water can be discharged from the annular gap through the annular plate communication portion to the scroll flow path. The condensed water discharged from the annular gap to the scroll passage through the annular plate communication portion flows through the scroll passage together with the exhaust gas flowing through the scroll passage or evaporates due to the heat of the exhaust gas. Therefore, in addition to suppressing accumulation of condensed water in the scroll gap between the housing main body and the scroll passage forming plate, condensed water is prevented from entering the annular gap between the closing member and the annular plate. Accumulation can also be suppressed.

In the above turbine housing, the exterior member includes a bottomed cylindrical housing main body portion having a plate-like bottom wall and a peripheral wall that is cylindrically erected from an outer peripheral portion of the bottom wall; and the housing main body portion. a closing member that closes the opening of the peripheral wall of the scroll passage, wherein the interior member includes a scroll passage forming plate that forms an inner wall of the scroll passage on the side of the housing main body; an annular plate forming an inner wall on the member side, wherein the gap includes an annular gap formed between the closing member and the annular plate, and the communicating portion is connected to the annular gap. It is preferable to include an annular plate communication portion that communicates with the scroll flow path.

Exhaust gas flows into an annular gap formed between the closing member and the annular plate, and heat is exchanged between the exhaust gas flowing into the annular gap and the closing member to cool the exhaust gas. Water vapor contained therein may condense to form condensed water in the annular space. Even in this case, the condensed water can be discharged from the annular gap through the annular plate communication portion to the scroll flow path. The condensed water discharged from the annular gap to the scroll passage through the annular plate communication portion flows through the scroll passage together with the exhaust gas flowing through the scroll passage or evaporates due to the heat of the exhaust gas. and the annular plate.

According to this invention, it is possible to suppress accumulation of condensed water in the gap between the exterior member and the interior member.

FIG. 2 is a side sectional view of the turbocharger in the first embodiment; FIG. 2 is a side sectional view showing an enlarged part of the turbocharger; FIG. 2 is a vertical cross-sectional view of the turbocharger; Sectional drawing which expands and shows a part of turbine housing. Sectional drawing which expands and shows a part of turbine housing in 2nd Embodiment. FIG. 4 is a side cross-sectional view showing an enlarged part of a turbocharger in another embodiment;

(First embodiment)
A first embodiment of a turbine housing used for a turbocharger will be described below with reference to FIGS. 1 to 4. FIG. The turbocharger of this embodiment is mounted on a vehicle. A turbocharger supercharges intake air to a vehicle engine.

As shown in FIG. 1 , the housing 11 of the turbocharger 10 has a bearing housing 20 , a turbine housing 30 and a compressor housing 40 . The bearing housing 20 and compressor housing 40 are cast. Exhaust gas discharged from the engine E flows inside the turbine housing 30 . Intake air directed to the engine E flows inside the compressor housing 40 .

A bearing housing 20 rotatably supports the impeller shaft 12 . A turbine wheel 13 is connected to one end of the impeller shaft 12 in the rotation axis direction. A compressor impeller 14 is connected to the other end of the impeller shaft 12 in the rotation axis direction. The turbine housing 30 is connected to one end of the impeller shaft 12 in the bearing housing 20 in the rotation axis direction. The compressor housing 40 is connected to the other end of the impeller shaft 12 in the bearing housing 20 in the rotation axis direction.

The bearing housing 20 has a cylindrical body portion 21 formed with an insertion hole 21h through which the impeller shaft 12 is inserted. The body portion 21 rotatably supports the impeller shaft 12 inserted through the insertion hole 21h via the radial bearing 15 . The axial direction of the body portion 21 coincides with the rotation axis direction of the impeller shaft 12 .

The body portion 21 has a large-diameter portion 211 and a small-diameter portion 212 that is continuous with one end of the large-diameter portion 211 in the rotation axis direction of the impeller shaft 12 and has an outer diameter smaller than that of the large-diameter portion 211 . . The main body portion 21 has a cylindrical projecting portion 22 projecting from one end surface 21 a of the small diameter portion 212 located in the rotation axis direction of the impeller shaft 12 . The protruding portion 22 has a shape in which the outer diameter gradually decreases with increasing distance from the small diameter portion 212 in the rotation axis direction of the impeller shaft 12 . The insertion hole 21h opens to the tip surface 22a of the projecting portion 22. As shown in FIG. An annular protrusion 22b protruding from the tip surface 22a of the protrusion 22 is formed around the insertion hole 21h in the tip surface 22a of the protrusion 22 .

A large-diameter end surface 21b of the large-diameter portion 211 located on the compressor housing 40 side in the rotational axis direction of the impeller shaft 12 is formed with a housing recess 23 . The insertion hole 21h opens to the bottom surface of the housing recess 23. As shown in FIG. The hole diameter of the accommodation recess 23 is larger than the hole diameter of the insertion hole 21h. The axis of the accommodation recess 23 coincides with the axis of the insertion hole 21h. A thrust bearing 16 is housed in the housing recess 23 . The thrust bearing 16 is housed in the housing recess 23 while being in contact with the bottom surface of the housing recess 23 .

The bearing housing 20 includes a small-diameter flange portion 24 protruding radially outward of the impeller shaft 12 from the outer peripheral surface of the small-diameter portion 212 , and an end portion of the outer peripheral surface of the large-diameter portion 211 opposite to the small-diameter portion 212 . It has 12 large-diameter side flange portions 25 protruding radially outward. The small diameter side flange portion 24 and the large diameter side flange portion 25 are each annular.

The compressor housing 40 has a bottomed cylindrical compressor main body 41 . The compressor main body 41 has a substantially disk-shaped bottom wall 41a and a cylindrical peripheral wall 41b erected in the direction of the rotation axis of the impeller shaft 12 from the peripheral edge of the bottom wall 41a. One surface of the peripheral wall 41b opposite to the bottom wall 41a is open. The compressor housing 40 is connected to the other end of the impeller shaft 12 in the bearing housing 20 in the rotation axis direction by attaching the opening-side end of the peripheral wall 41b to the large-diameter flange portion 25 with screws (not shown). . The opening of the peripheral wall 41b is closed by the large-diameter end surface 21b of the body portion 21 and the end surface of the large-diameter flange portion 25 opposite to the small-diameter flange portion 24 . That is, the opening of the peripheral wall 41b is closed by the end surface of the bearing housing 20 located at the other end of the impeller shaft 12 in the rotation axis direction.

The compressor housing 40 also has a compressor tubular portion 42 projecting from the bottom wall 41a to the side opposite to the peripheral wall 41b. The compressor tubular portion 42 has an intake port 42a. The intake port 42a extends in the rotational axis direction of the impeller shaft 12 . The axis of the intake port 42 a coincides with the rotational axis of the impeller shaft 12 .

A compressor impeller chamber 43 , a diffuser channel 44 , and a compressor scroll channel 45 are formed in the compressor housing 40 . The compressor impeller chamber 43 accommodates the compressor impeller 14 while communicating with the intake port 42a. The compressor scroll flow path 45 spirally circulates around the compressor impeller chamber 43 . The diffuser flow path 44 extends annularly around the compressor impeller chamber 43 and communicates the compressor scroll flow path 45 with the compressor impeller chamber 43 .

A cylindrical shroud member 46 is provided within the compressor housing 40 . The shroud member 46 has a tubular portion 46a extending along the inner peripheral surface of the compressor tubular portion 42, and an annular portion 46b continuous with the tubular portion 46a and annularly extending along the inner bottom surface of the bottom wall 41a. ing. The compressor impeller chamber 43 is a space surrounded by the cylindrical portion 46 a of the shroud member 46 and the housing recess 23 of the bearing housing 20 .

The compressor impeller 14 extends in the rotational axis direction of the impeller shaft 12 and has a shaft insertion hole 14h through which the impeller shaft 12 can be inserted. The other end of the impeller shaft 12 in the rotation axis direction protrudes into the compressor impeller chamber 43 . The compressor impeller 14 is attached to the impeller shaft 12 via a nut or the like so that it can rotate integrally with the impeller shaft 12 in a state in which the portion of the impeller shaft 12 protruding into the compressor impeller chamber 43 is inserted into the shaft insertion hole 14h. is attached to the impeller shaft 12. The end of the compressor impeller 14 on the bearing housing 20 side is supported by a thrust bearing 16 via a seal ring collar, a thrust collar, or the like (not shown). The thrust bearing 16 receives a thrust-direction load acting on the compressor impeller 14 .

A surface 46 c of the annular portion 46 b of the shroud member 46 facing the bearing housing 20 is a flat surface extending in the radial direction of the impeller shaft 12 . The diffuser flow path 44 includes a surface 46c of the annular portion 46b and an end surface located at the other end of the bearing housing 20 in the rotation axis direction of the impeller shaft 12. It is formed between the parts facing each other in the rotation axis direction.

An annular compressor scroll member 47 is provided in the compressor housing 40 . A compressor scroll member 47 extends around the shroud member 46 . The compressor scroll passage 45 is formed by the outer peripheral surface of the annular portion 46 b of the shroud member 46 , the inner bottom surface of the bottom wall 41 a of the compressor main body 41 , and the inner peripheral surface of the compressor scroll member 47 . Note that the compressor scroll member 47 and the shroud member 46 may be integrally formed with the compressor housing 40 instead of being separate members from the compressor housing 40 .

As shown in FIGS. 2 and 3, the turbine housing 30 is formed of a cast exterior member 30a and a sheet metal interior member 30b housed in the exterior member 30a. The exterior member 30a accommodates the interior member 30b with a gap G interposed therebetween.

The exterior member 30 a has a bottomed cylindrical housing body portion 31 and a closing member 38 . The housing main body 31 has a substantially disk-shaped bottom wall 31a and a cylindrical peripheral wall 31b extending from the outer peripheral portion of the bottom wall 31a in the rotational axis direction of the impeller shaft 12 . One surface of the peripheral wall 31b opposite to the bottom wall 31a is open.

As shown in FIG. 2, an annular flange portion 31f that protrudes radially outward from the impeller shaft 12 is formed at the opening-side end portion of the outer peripheral surface of the peripheral wall 31b. An end face 31c of the flange portion 31f opposite to the bottom wall 31a is located closer to the bearing housing 20 than an end face 31d of the peripheral wall 31b on the opening side. An end surface 31c of the flange portion 31f and an end surface 31d of the peripheral wall 31b are flat surfaces extending in the radial direction of the impeller shaft 12 .

As shown in FIGS. 1 and 2, the closing member 38 closes the opening of the peripheral wall 31b of the housing main body 31. As shown in FIGS. The closing member 38 has a bottomed cylindrical shape having a substantially disk-shaped bottom wall 38a and a peripheral wall 38b that is cylindrically erected from the outer peripheral portion of the bottom wall 38a. A through hole 38h is formed in the central portion of the bottom wall 38a. The direction in which the axis of the through hole 38h extends coincides with the axial direction of the peripheral wall 38b. The closing member 38 also has an annular flange portion 38c extending radially outward of the impeller shaft 12 from the end portion of the outer peripheral surface of the peripheral wall 38b opposite to the bottom wall 38a. The opening end of the peripheral wall 38b is a protruding portion 38d that protrudes from the end surface 381 of the flange portion 38c on the side opposite to the bottom wall 38a. Further, the closing member 38 has a tubular extending portion 38e extending in the rotation axis direction of the impeller shaft 12 from the periphery of the through hole 38h on the outer surface of the bottom wall 38a. The blocking member 38 has an annular projecting portion 38f projecting radially outward of the impeller shaft 12 from the end portion of the outer peripheral surface of the extending portion 38e opposite to the bottom wall 38a.

The closing member 38 is connected to the body portion 21 by clamping force of the clamp member 39 between the small-diameter side flange portion 24 of the body portion 21 of the bearing housing 20 and the projecting portion 38f. The projecting portion 22 of the main body portion 21 is inserted into the through hole 38h of the closing member 38 . In a state in which the closing member 38 is connected to the body portion 21 , the closing member 38 is positioned so as to surround the protruding portion 22 of the body portion 21 .

In the turbine housing 30, the flange portion 31f and the flange portion 38c are attached with the screws 17 in a state in which the end surface 31c of the flange portion 31f and the end surface 381 of the flange portion 38c of the closing member 38 are in contact with each other. It is connected to one end of the impeller shaft 12 in the rotation axis direction.

A seal member 18 is provided between the end face 31c of the flange portion 31f and the end face 381 of the closing member 38. As shown in FIG. The sealing member 18 seals between the end face 31c of the flange portion 31f and the end face 381 of the closing member 38. As shown in FIG.

The exterior member 30a has a turbine tubular portion 32 projecting from the bottom wall 31a to the side opposite to the peripheral wall 31b. A discharge port 32 a is formed in the turbine tubular portion 32 . The discharge port 32 a extends in the rotational axis direction of the impeller shaft 12 . The axial center of the discharge port 32 a coincides with the rotational axis of the impeller shaft 12 . An open end surface 32 e of the turbine tubular portion 32 is a flat surface extending in the radial direction of the impeller shaft 12 .

An annular connecting flange 32 f protrudes from the opening-side end of the outer peripheral surface of the turbine tubular portion 32 . A downstream side exhaust pipe 19 is connected to the discharge port 32a. The downstream exhaust pipe 19 is connected to the turbine tubular portion 32 by sandwiching the connecting flange 19f of the downstream exhaust pipe 19 and the connecting flange 32f of the turbine tubular portion 32 with the clamp member 19c. Concatenated. An end face 19 e of the downstream exhaust pipe 19 on the turbine tubular portion 32 side has a flat surface shape extending parallel to the opening end face 32 e of the turbine tubular portion 32 .

The downstream exhaust pipe 19 connects the turbocharger 10 and a catalyst C1 provided downstream of the turbine housing 30 in the flow direction of the exhaust gas. The catalyst C1 purifies exhaust gas. When the temperature of the catalyst C1 rises above the activation temperature, the catalyst C1 exerts its ability to purify the exhaust gas.

A turbine chamber 33 , a communication channel 34 , and a turbine scroll channel 35 are formed in the turbine housing 30 . The turbine scroll passage 35 is a scroll passage through which the exhaust gas discharged from the engine E flows. Turbine wheel 13 is housed in turbine chamber 33 . The turbine scroll passage 35 spirally circulates around the outer circumference of the turbine chamber 33 . Therefore, the turbine scroll passage 35 is formed so as to surround the turbine chamber 33 and the turbine wheel 13 . The turbine scroll channel 35 is part of a channel that guides the exhaust gas that has flowed into the turbine housing 30 to the turbine chamber 33 . The communication passage 34 extends annularly around the turbine chamber 33 and communicates the turbine scroll passage 35 with the turbine chamber 33 .

The turbocharger 10 has a plurality of nozzle vanes 50, a first plate 51 and a second plate 52. As shown in FIG. The plurality of nozzle vanes 50 make the passage area of the communication passage 34 variable and adjust the flow velocity of the exhaust gas guided to the turbine chamber 33 . The plurality of nozzle vanes 50 are arranged at intervals in the circumferential direction of the communication channel 34 .

The first plate 51 is arranged inside the peripheral wall 38 b of the closing member 38 and extends annularly around the projecting portion 22 of the bearing housing 20 . The first plate 51 rotatably supports the nozzle vanes 50 and forms a wall surface of the communication passage 34 on the side of the bearing housing 20 . The first plate 51 has an annular convex portion 51 f that protrudes radially inward of the impeller shaft 12 from the inner peripheral surface of the first plate 51 . The convex portion 51f faces the projecting portion 22 in the rotation axis direction of the impeller shaft 12 .

The second plate 52 has a cylindrical portion 52a extending along the inner peripheral surface of the turbine cylindrical portion 32, and an annular portion 52b continuous with the cylindrical portion 52a and extending along the inner bottom surface 31e of the bottom wall 31a. ing. The turbine chamber 33 is a space surrounded by the cylindrical portion 52a of the second plate 52, the convex portion 51f of the first plate 51, and the tip surface 22a of the projecting portion 22 of the bearing housing 20. As shown in FIG. The turbine chamber 33 communicates with the discharge port 32a. The exhaust gas that has passed through the turbine chamber 33 is guided to the discharge port 32a.

The annular portion 52b of the second plate 52 is arranged to face the first plate 51 in the rotation axis direction of the impeller shaft 12, and cooperates with the first plate 51 to rotatably support the plurality of nozzle vanes 50. As shown in FIG. The annular portion 52 b forms a wall surface of the communication passage 34 on the side opposite to the bearing housing 20 . The distance between the first plate 51 and the annular portion 52b of the second plate 52 in the rotation axis direction of the impeller shaft 12 is maintained by a plurality of columnar spacers 53. As shown in FIG. The plurality of spacers 53 are arranged at intervals in the circumferential direction of the communication channel 34 . Note that the plurality of nozzle vanes 50 are driven by a link member (not shown).

The turbine wheel 13 has a fitting protrusion 13f that protrudes toward the insertion hole 21h. One end surface of the impeller shaft 12 in the rotation axis direction is formed with a fitting recess 12f into which the fitting projection 13f can be fitted. The turbine wheel 13 is attached to the impeller shaft 12 by welding or the like so that the turbine wheel 13 can rotate integrally with the impeller shaft 12 with the fitting projections 13f fitted into the fitting recesses 12f of the impeller shaft 12. installed. The turbine wheel 13 is rotated by the exhaust gas introduced into the turbine chamber 33 , and the impeller shaft 12 rotates together with the rotation of the turbine wheel 13 .

An annular plate spring 55 is attached to the convex portion 22 b of the protrusion portion 22 . The outer peripheral edge of the plate spring 55 abuts the end surface of the projection 51 f of the first plate 51 on the bearing housing 20 side. The leaf spring 55 biases the first plate 51 toward the side opposite to the bearing housing 20 . Thereby, the first plate 51 , the plurality of spacers 53 , and the second plate 52 are supported by the bottom wall 31 a of the housing body 31 while being pressed against the bottom wall 31 a.

The exterior member 30 a has a bulging wall 36 that bulges toward the side opposite to the bearing housing 20 and surrounds the turbine tubular portion 32 on the outer peripheral portion of the bottom wall 31 a of the housing main body 31 . . The bulging wall 36 has a bulging outer peripheral wall 36a, a bulging inner peripheral wall 36b, and a bulging connecting wall 36c. The bulging outer peripheral wall 36 a continues to the end of the peripheral wall 31 b of the housing body 31 opposite to the opening side and extends in the rotational axis direction of the impeller shaft 12 . The bulging inner peripheral wall 36b is positioned inside the bulging outer peripheral wall 36a and continues to a portion of the bottom wall 31a radially inward of the impeller shaft 12 relative to the bulging wall 36. As shown in FIG. The bulging connecting wall 36c has a shape curved in an arc that protrudes toward the side opposite to the bearing housing 20, and the bulging outer peripheral wall 36a and the bulging inner peripheral wall 36b is connected to the edge opposite to the bearing housing 20 in the .

The interior member 30b has a scroll passage forming plate 60 made of sheet metal. The thickness of the scroll flow path forming plate 60 is thinner than the thicknesses of the first plate 51 and the second plate 52 . The scroll flow path forming plate 60 spirally surrounds the outer circumference of the turbine chamber 33 . The scroll flow path forming plate 60 has an outer peripheral wall 61 , an inner peripheral wall 62 , a connecting wall 63 and an inner peripheral edge 64 .

The outer peripheral wall 61 surrounds the outer periphery of the turbine chamber 33 outside the second plate 52 in the radial direction of the impeller shaft 12 and forms the outer peripheral side inner surface 35 a of the turbine scroll flow path 35 . The outer peripheral wall 61 extends along the inner peripheral surface 310 of the peripheral wall 31b of the housing body portion 31 and the inner peripheral surface of the bulging outer peripheral wall 36a. The outer peripheral surface 61a of the outer peripheral wall 61 is separated from the inner peripheral surface 310 of the peripheral wall 31b and the inner peripheral surface of the bulging outer peripheral wall 36a.

The inner peripheral wall 62 is located inside the outer peripheral wall 61 and forms an inner peripheral side inner surface 35 b of the turbine scroll flow path 35 . The inner peripheral wall 62 extends along the inner peripheral surface of the bulging inner peripheral wall 36b. The outer peripheral surface 62a of the inner peripheral wall 62 is separated from the inner peripheral surface of the bulging inner peripheral wall 36b. The inner peripheral surface of the inner peripheral wall 62 forming the inner peripheral side inner surface 35b of the turbine scroll passage 35 is located at substantially the same position in the radial direction of the impeller shaft 12 as the outer peripheral edge of the annular portion 52b of the second plate 52 .

The connecting wall 63 connects the edge of the outer peripheral wall 61 opposite to the bearing housing 20 and the edge of the inner peripheral wall 62 opposite to the bearing housing 20 . The connecting wall 63 extends along the inner peripheral surface of the bulging connecting wall 36 c and has an arcuate curved shape that protrudes toward the side opposite to the bearing housing 20 . The outer peripheral surface 63a of the connecting wall 63 is separated from the inner peripheral surface of the bulging connecting wall 36c.

The inner peripheral edge 64 extends radially inward of the impeller shaft 12 from the edge of the inner peripheral wall 62 on the bearing housing 20 side. The inner peripheral edge 64 extends between the bottom wall 31 a of the housing main body 31 and the annular portion 52 b of the second plate 52 in the rotation axis direction of the impeller shaft 12 . The inner peripheral edge 64 is sandwiched between the bottom wall 31 a and the annular portion 52 b by the biasing force of the plate spring 55 . In other words, the inner peripheral edge 64 of the scroll passage forming plate 60 is sandwiched between the turbine housing 30 and the second plate 52 .

The turbine housing 30 has a scroll gap 65 formed between the housing main body 31 and the scroll passage forming plate 60 . Therefore, the scroll gap 65 is the gap G formed between the exterior member 30a and the interior member 30b. Therefore, the gap G includes a scroll gap 65 formed between the housing main body 31 and the scroll passage forming plate 60 . The scroll gap 65 is a scroll heat insulating layer formed between the housing main body 31 and the scroll passage forming plate 60 . The scroll gap 65 blocks heat transfer from the scroll passage forming plate 60 to the housing main body 31 .

A scroll elastic member 66 is interposed between the end portion of the outer peripheral surface 61 a of the outer peripheral wall 61 opposite to the connecting wall 63 and the housing body portion 31 . The scroll elastic member 66 is positioned within the scroll gap 65 . The scroll elastic member 66 is an annular wire mesh attached to the outer peripheral surface 61 a of the outer peripheral wall 61 . The scroll elastic member 66 is arranged in a crushed state between the outer peripheral surface 61 a of the outer peripheral wall 61 and the inner peripheral surface 310 of the peripheral wall 31 b of the housing body portion 31 . The scroll elastic member 66 is welded to the outer peripheral surface 61a of the outer peripheral wall 61 by micro spot welding, for example. The outer peripheral wall 61 is supported by the housing main body 31 via a scroll elastic member 66 .

The scroll flow path forming plate 60 has an annular flange portion 67 protruding radially outward of the impeller shaft 12 from the edge of the outer peripheral wall 61 opposite to the connecting wall 63 . The flange portion 67 extends toward the opening-side end portion of the inner peripheral surface 310 of the peripheral wall 31 b of the housing body portion 31 . There is a gap between the tip of the flange portion 67 in the projecting direction and the inner peripheral surface 310 of the peripheral wall 31b, and the flange portion 67 and the peripheral wall 31b are not in contact with each other.

The scroll passage forming plate 60 has a scroll communicating portion H1. The scroll communicating portion H1 is a notch formed from a portion of the flange portion 67 of the scroll passage forming plate 60 to a portion of the edge of the outer peripheral wall 61 opposite to the communicating wall 63 . The scroll communicating portion H1 penetrates the flange portion 67 and the outer peripheral wall 61 in their thickness directions. The scroll communication portion H<b>1 communicates the scroll gap portion 65 and the turbine scroll passage 35 .

As shown in FIGS. 3 and 4, the turbocharger 10 is mounted on the vehicle such that the rotation axis of the impeller shaft 12 extends in the horizontal direction and the scroll communication portion H1 is positioned at the lowest portion 600 of the scroll passage forming plate 60. is installed. Therefore, the scroll communicating portion H1 is formed at the lowermost portion 600 of the scroll passage forming plate 60. As shown in FIG. The scroll communicating portion H1 opens at the lowest portion 610a of the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll passage forming plate 60, and faces the lowest portion 310a of the inner peripheral surface 310 of the peripheral wall 31b of the housing main body portion 31. there is The axis L of the turbine wheel 13 coincides with the rotation axis of the impeller shaft 12 . Therefore, the axis L of the turbine wheel 13 extends horizontally. The scroll communicating portion H1 is formed at a portion of the scroll flow passage forming plate 60 located vertically below the axis L of the turbine wheel 13 extending in the horizontal direction.

As shown in FIG. 4, the scroll gap portion 65 is defined by the scroll communicating portion H1, which is the distance between the inner peripheral surface 310 of the peripheral wall 31b of the housing main body portion 31 and the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll passage forming plate 60. It has a gap reduction portion R that gradually becomes shorter as it approaches . The gap reduction portion R is formed between the inner peripheral surface 310 of the peripheral wall 31b of the housing main body portion 31 and the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll flow path forming plate 60 while passing below the scroll communicating portion H1. It extends from the communication portion H1 to both sides in the circumferential direction of the peripheral wall 31b of the housing body portion 31 .

In the gap reduction portion R, the distance L1 between the lowest portion 310a of the inner peripheral surface 310 of the peripheral wall 31b of the housing body portion 31 and the lowest portion 610a of the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll passage forming plate 60 is It is the shortest between the inner peripheral surface 310 of the peripheral wall 31b of the body portion 31 and the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll flow path forming plate 60 . In the gap reduction portion R, the distance between the inner peripheral surface 310 of the peripheral wall 31b of the housing main body portion 31 and the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll passage forming plate 60 is set apart from the lowermost portions 310a and 610a. It gradually gets longer as you go. Therefore, as the distance between the inner peripheral surface 310 of the peripheral wall 31b of the housing main body 31 and the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll flow path forming plate 60 approaches the scroll communication portion H1, the air gap reduction portion R gradually increases. getting shorter.

As shown in FIG. 2, the interior member 30b has an annular plate 70 made of sheet metal. The annular plate 70 is arranged around the first plate 51 and faces most of the connecting wall 63 of the scroll passage forming plate 60 in the rotation axis direction of the impeller shaft 12 . The thickness of the annular plate 70 is thinner than the thicknesses of the first plate 51 and the second plate 52 .

The turbine scroll channel 35 is formed by an outer peripheral wall 61 , an inner peripheral wall 62 and a connecting wall 63 of the scroll channel forming plate 60 and a portion of the annular plate 70 facing the connecting wall 63 . Therefore, the scroll passage forming plate 60 forms the inner wall of the turbine scroll passage 35 on the housing main body 31 side, and the annular plate 70 forms the inner wall of the turbine scroll passage 35 on the closing member 38 side. Therefore, the interior member 30b forms at least the inner wall of the turbine scroll passage 35. As shown in FIG.

The outer peripheral edge 71 of the annular plate 70 extends between the end face 31d of the peripheral wall 31b and the end face 380 of the protrusion 38d. The outer peripheral edge 71 of the annular plate 70 is sandwiched between the end face 31d of the peripheral wall 31b and the end face 380 of the projecting portion 38d by the fastening force of the screw 17. As shown in FIG. That is, the outer peripheral edge 71 of the annular plate 70 is sandwiched between the housing body portion 31 and the closing member 38 .

The turbine housing 30 has an annular gap 74 formed between the peripheral wall 38 b of the closing member 38 and the annular plate 70 . Therefore, the annular gap 74 is the gap G formed between the exterior member 30a and the interior member 30b. Accordingly, the gap G includes an annular gap 74 formed between the closure member 38 and the annular plate 70 . The annular gap 74 is a scroll heat insulating layer formed between the closure member 38 and the annular plate 70 . The annular gap 74 blocks heat transfer from the annular plate 70 to the closure member 38 .

The annular plate 70 has a cylindrical rib 73 protruding from an inner peripheral portion 72 of the annular plate 70 toward the side opposite to the scroll flow path forming plate 60 in the rotational axis direction of the impeller shaft 12 . The rib 73 extends along the outer peripheral edge of the first plate 51 . There is a slight gap between the inner peripheral surface of the rib 73 and the outer peripheral edge of the first plate 51 , and the rib 73 is out of contact with the first plate 51 .

As shown in FIGS. 1 and 2, the turbocharger 10 includes a tubular discharge port forming member 80 made of sheet metal that forms the wall surface of the discharge port 32a. The discharge port forming member 80 includes a cylindrical discharge port body wall 81 that forms the wall surface of the discharge port 32a, and extends radially outward of the impeller shaft 12 from the edge of the discharge port body wall 81 on the side opposite to the turbine chamber 33. and an annular outlet outer peripheral edge 82 extending toward.

An end portion 81 a of the outlet main body wall 81 on the turbine chamber 33 side surrounds an end portion of the cylindrical portion 52 a of the second plate 52 opposite to the annular portion 52 b. A discharge port elastic member 83 is interposed between the turbine chamber 33 side end of the outer peripheral surface 81 b of the discharge port main body wall 81 and the inner peripheral surface of the turbine tubular portion 32 . The outlet elastic member 83 is an annular wire mesh attached to the outer peripheral surface 81 b of the outlet main body wall 81 . The discharge port elastic member 83 is arranged in a crushed state between the outer peripheral surface 81 b of the discharge port body wall 81 and the inner peripheral surface of the turbine tubular portion 32 . The outlet elastic member 83 is welded to the outer peripheral surface 81b of the outlet main body wall 81 by, for example, micro-spot welding. The discharge port main body wall 81 is supported by the turbine tubular portion 32 via a discharge port elastic member 83 .

The discharge port outer peripheral edge 82 protrudes from the opening of the turbine tubular portion 32 and extends along the opening end surface 32 e of the turbine tubular portion 32 . The discharge port outer peripheral edge 82 is sandwiched between the opening end face 32e of the turbine tubular portion 32 and the end face 19e of the downstream exhaust pipe 19 by the fastening force of the clamp member 19c. That is, the discharge port outer peripheral edge 82 is sandwiched between the turbine housing 30 and the downstream side exhaust pipe 19 .

The turbocharger 10 has a discharge port air layer 84 formed between the outer peripheral surface 81b of the discharge port main body wall 81 and the inner peripheral surface of the turbine tubular portion 32 . The outlet air layer 84 is an outlet heat insulating layer formed between the outlet forming member 80 and the exterior member 30a. The outlet air layer 84 blocks heat transfer from the outlet forming member 80 to the turbine tubular portion 32 .

As shown in FIG. 3 , the exterior member 30 a has a tubular introduction portion forming portion 37 protruding from the outer peripheral surface of the housing body portion 31 . In addition, in FIG. 3, illustration of the second plate 52 and the turbine wheel 13 is omitted for convenience of explanation.

Further, the interior member 30 b has a tubular introduction passage forming plate 90 made of sheet metal that forms the inner wall of the introduction passage 37 a that introduces the exhaust gas into the turbine scroll passage 35 . The introduction channel forming plate 90 includes a cylindrical main body portion 90a whose inner diameter and outer diameter gradually increase from one end to the other end, and an annular shape projecting outward from the other end of the cylindrical main body portion 90a. and a flange portion 90f. One end of the cylindrical body portion 90 a is one end of the introduction channel forming plate 90 , and the flange portion 90 f is the other end of the introduction channel forming plate 90 .

The inner peripheral surface 370 of the introduction portion forming portion 37 extends along the outer peripheral surface 900 of the tubular body portion 90a. The introduction channel forming plate 90 is inserted into the introduction portion forming portion 37 from one end side of the cylindrical body portion 90a. Therefore, the introduction part forming part 37 accommodates the introduction channel forming plate 90 . The introduction channel 37 a is formed inside the introduction portion forming portion 37 . Therefore, the introduction passage 37 a is formed inside the turbine housing 30 .

The scroll flow path forming plate 60 has a cylindrical portion 68 into which the exhaust gas from the introduction flow path 37a is introduced. The tubular portion 68 communicates with the turbine scroll passage 35 . One end of the tubular body portion 90 a of the introduction channel forming plate 90 is inserted inside the tubular portion 68 . One end of the tubular body portion 90 a of the introduction channel forming plate 90 is surrounded by the tubular portion 68 . One end of the introduction channel forming plate 90 is not fixed to the scroll channel forming plate 60 and is a free end. The introduction flow path 37 a and the turbine scroll flow path 35 communicate with each other via the cylindrical portion 68 .

The turbine housing 30 includes an introduction section gap 92 formed between an inner peripheral surface 370 of the introduction section forming section 37 and an outer peripheral surface 900 of a cylindrical main body section 90 a of the introduction passage forming plate 90 . Therefore, the introduction part gap part 92 is the gap part G formed between the exterior member 30a and the interior member 30b. Therefore, the gap G includes an introduction part gap 92 formed between the introduction part forming part 37 and the introduction channel forming plate 90 . The introduction section cavity 92 is an introduction section heat insulating layer formed between the introduction passage forming plate 90 and the introduction section forming section 37 . The introduction section gap 92 blocks the transfer of heat from the introduction channel forming plate 90 to the introduction section forming section 37 .

An introduction section elastic member 93 is interposed between a portion of the outer peripheral surface 900 of the tubular main body 90 a of the introduction passage forming plate 90 near one end and the inner peripheral surface 370 of the introduction section forming section 37 . The introduction section elastic member 93 is an annular wire mesh attached to the outer peripheral surface 900 of the tubular body section 90 a of the introduction channel forming plate 90 . The introduction section elastic member 93 is arranged in a crushed state between the outer peripheral surface 900 of the cylindrical main body section 90 a of the introduction passage forming plate 90 and the inner peripheral surface 370 of the introduction section forming section 37 . The introduction section elastic member 93 is welded to the outer peripheral surface 900 of the cylindrical body section 90a of the introduction channel forming plate 90 by, for example, micro spot welding. The introduction passage forming plate 90 is supported by the introduction portion forming portion 37 via the introduction portion elastic member 93 .

An end portion of the introduction portion forming portion 37 opposite to the housing main body portion 31 forms an annular flange portion 37f. The opening of the introduction portion forming portion 37 on the side opposite to the housing main body portion 31 is continuous with the end surface 371 of the flange portion 37f. Further, the opening of the introduction portion forming portion 37 on the side opposite to the housing main body portion 31 has a stepped surface 372 that is continuous with the end surface 371 of the flange portion 37f.

The flange portion 90 f of the introduction passage forming plate 90 extends along the step surface 372 of the introduction portion forming portion 37 . The flange portion 90 f is sandwiched between the end surface 94 e of the upstream exhaust pipe 94 connected to the introduction portion forming portion 37 and the stepped surface 372 of the introduction portion forming portion 37 . Specifically, the flange portion 90f is connected to the end surface 94e of the upstream exhaust pipe 94 and the stepped surface 372 of the introduction portion forming portion 37 by the fastening force of screws (not shown) that fasten the upstream exhaust pipe 94 and the flange portion 90f. is sandwiched between Therefore, the other end of the introduction channel forming plate 90 is a fixed end.

In this embodiment, the turbine scroll flow path 35 is formed by the scroll flow path forming plate 60 and the annular plate 70 that constitute the interior member 30b and the portion of the housing main body 31 of the exterior member 30a that accommodates the scroll flow path forming plate 60. A spiral scroll portion S forming a is configured. Further, in the present embodiment, an introduction portion I that forms an introduction passage 37a is configured by the introduction passage forming plate 90 that constitutes the interior member 30b and the introduction portion forming portion 37 of the exterior member 30a. Therefore, the scroll portion S and the introduction portion I are formed by the exterior member 30a and the interior member 30b accommodated in the exterior member 30a.

The upstream exhaust pipe 94 introduces the exhaust gas discharged from the engine E into the introduction passage 37a. The exhaust gas introduced into the introduction passage 37a passes through the inside of the cylindrical portion 68, the turbine scroll passage 35, the communication passage 34, the turbine chamber 33, the discharge port 32a, and the inside of the downstream side exhaust pipe 19. to the catalyst C1. Therefore, the inside of the upstream side exhaust pipe 94, the introduction passage 37a, the inside of the cylindrical portion 68, the turbine scroll passage 35, the communication passage 34, the turbine chamber 33, the discharge port 32a, and the inside of the downstream side exhaust pipe 19 are , form an exhaust passage 95 through which the exhaust gas discharged from the engine E flows. Therefore, the turbine scroll flow path 35 and the introduction flow path 37 a are part of the exhaust passage 95 . The scroll communication portion H1 is a communication portion H that allows communication between the scroll gap portion 65 that is the gap portion G and the turbine scroll passage 35 that is a part of the exhaust passage 95 . Therefore, the interior member 30b has a communicating portion H that communicates the gap portion G and the exhaust passage 95 with each other. The communicating portion H includes a scroll communicating portion H1. The communication portion H is formed in a portion of the interior member 30b located below the axis L of the turbine wheel 13 extending in the horizontal direction in the vertical direction.

When exhaust gas is introduced into the turbine chamber 33 , the turbine wheel 13 is rotated by the exhaust gas introduced into the turbine chamber 33 . As the turbine wheel 13 rotates, the compressor impeller 14 rotates integrally with the turbine wheel 13 via the impeller shaft 12 . When the compressor impeller 14 rotates, the intake air introduced into the compressor impeller chamber 43 through the intake port 42a is compressed by the rotation of the compressor impeller 14 and decelerated when passing through the diffuser passage 44, resulting in the intake air speed Energy is converted into pressure energy. Then, the high-pressure intake air is discharged to the compressor scroll passage 45 and supplied to the engine E. By supercharging the intake air to the engine E by the turbocharger 10 in this manner, the intake efficiency of the engine E is increased, and the performance of the engine E is improved.

Next, operation of the first embodiment will be described.
Since the introduction channel forming plate 90, the scroll channel forming plate 60, the annular plate 70, and the discharge port forming member 80 suppress heat transfer of the exhaust gas to the exterior member 30a, the exhaust gas flows through the turbine housing 30. It is difficult for heat to be lost between them, making it difficult for the temperature to drop. As a result, the time required for the temperature of the catalyst C1 to rise above the activation temperature is shortened. Therefore, for example, under operating conditions that require early warm-up of the catalyst C1, such as when the engine E is cold-started, the temperature of the catalyst C1 tends to rise quickly to the activation temperature or higher.

By the way, the exhaust gas discharged from the engine E contains water vapor. Exhaust gas discharged from the engine E flows from the upstream side exhaust pipe 94 into the introduction passage 37 a and is introduced into the turbine scroll passage 35 via the cylindrical portion 68 from the introduction passage 37 a. Here, the scroll passage forming plate 60 is warmed by the heat of the exhaust gas. Heat is less likely to be transferred from the housing 60 to the housing main body 31 . Therefore, there is a temperature difference between the housing main body 31 and the scroll flow path forming plate 60 , and the temperature of the housing main body 31 is lower than that of the scroll flow path forming plate 60 .

At this time, for example, when exhaust gas flows into the scroll gap 65 between the housing main body 31 and the scroll passage forming plate 60 , heat exchange occurs between the exhaust gas flowing into the scroll gap 65 and the housing main body 31 . As a result, the exhaust gas is cooled, and water vapor contained in the exhaust gas is condensed, and condensed water W may be generated in the scroll gap portion 65 . The condensed water W produced in this manner moves along the inner peripheral surface 310 of the peripheral wall 31b of the housing main body 31 and the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll flow path forming plate 60 by its own weight, and moves downward through the scroll gap 65 in the vertical direction. flowing. Then, the condensed water W accumulated in the lowermost portion of the scroll gap portion 65 is discharged to the turbine scroll flow path 35 via the scroll communication portion H1. The condensed water W discharged from the scroll gap 65 to the turbine scroll passage 35 via the scroll communication portion H1 flows through the turbine scroll passage 35 together with the exhaust gas flowing through the turbine scroll passage 35, or is evaporated by the heat of the exhaust gas. Therefore, accumulation of condensed water W in the scroll gap portion 65 is suppressed.

The following effects can be obtained in the first embodiment.
(1-1) Even if the water vapor contained in the exhaust gas is condensed and the condensed water W is generated in the scroll gap 65, the condensed water W is discharged from the scroll gap 65 through the scroll communicating portion H1 to the turbine scroll passage. 35 can be discharged. The condensed water W discharged from the scroll gap 65 to the turbine scroll passage 35 via the scroll communication portion H1 flows through the turbine scroll passage 35 together with the exhaust gas flowing through the turbine scroll passage 35, or is heated by the heat of the exhaust gas. evaporate. Therefore, it is possible to prevent the condensed water W from accumulating in the scroll gap 65 between the exterior member and the scroll passage forming plate 60 .

(1-2) The scroll communicating portion H1 is formed at a portion of the scroll passage forming plate 60 located vertically below the axis L of the horizontally extending turbine wheel 13 . As a result, the condensed water W flowing vertically downward through the scroll gap 65 due to its own weight is easily discharged from the scroll gap 65 to the turbine scroll passage 35 via the scroll communicating portion H1. Therefore, the condensed water W generated in the scroll gap portion 65 can be efficiently discharged from the scroll gap portion 65 to the turbine scroll passage 35 via the scroll communicating portion H1. It can be easily suppressed to put away.

(1-3) The condensed water W generated in the scroll gap 65 flows vertically downward through the scroll gap 65 due to its own weight. Easy to collect at the bottom. At this time, since the scroll communicating portion H1 is formed at the lowest portion of the scroll passage forming plate 60, the condensed water W accumulated in the lowest portion of the scroll gap portion 65 flows from the scroll gap portion 65 through the scroll communicating portion H1. is easily discharged to the turbine scroll passage 35. Therefore, the condensed water W generated in the scroll gap portion 65 can be efficiently discharged from the scroll gap portion 65 to the turbine scroll passage 35 via the scroll communicating portion H1. It can be easily suppressed to put away.

(1-4) In the scroll gap portion 65, the distance between the inner peripheral surface 310 of the peripheral wall 31b of the housing body portion 31 and the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll passage forming plate 60 approaches the scroll communicating portion H1. It has a gap narrowing portion R that gradually becomes shorter as it increases. According to this, compared with the structure in which the scroll gap 65 does not have the gap reduction portion R, the volume of the portion of the scroll gap 65 below the scroll communicating portion H1 in the vertical direction becomes smaller. Therefore, the condensed water accumulated in the lowermost portion of the scroll gap 65 is more easily discharged from the scroll gap 65 to the turbine scroll passage 35 via the scroll communicating portion H1. Therefore, the condensed water W generated in the scroll gap portion 65 can be more efficiently discharged from the scroll gap portion 65 to the turbine scroll passage 35 via the scroll communicating portion H1. It is possible to further easily suppress the fact that

(1-5) In general, since the exterior member 30a of the turbine housing 30 needs to ensure rigidity, it is formed thick by casting, so that it has a large mass and a large heat capacity. Therefore, in the turbine housing 30 of the present embodiment, the interior member 30b made of sheet metal is accommodated in the exterior member 30a, and the interior member 30b suppresses the heat transfer of the exhaust gas to the exterior member 30a. According to this, the temperature of the exhaust gas is prevented from decreasing while the exhaust gas flows through the turbine housing 30. Therefore, the time required for the temperature of the catalyst C1 to rise above the activation temperature can be shortened. can be done. Therefore, the temperature of the catalyst C1 can be quickly raised to the activation temperature or higher under operating conditions that require early warm-up of the catalyst C1, such as when the engine E is cold-started.

(Second embodiment)
A second embodiment in which the turbine housing is embodied will now be described with reference to FIG. In addition, in the embodiment described below, the same reference numerals are assigned to the same configurations as those of the already described first embodiment, and redundant description thereof will be omitted or simplified.

As shown in FIG. 5, the turbocharger 10 is arranged such that the rotation axis of the impeller shaft 12 extends in the horizontal direction, and the cylindrical body portion 90a of the introduction passage forming plate 90 opens downward in the vertical direction. installed in the vehicle. At this time, the axial direction of the cylindrical main body portion 90a coincides with the vertical direction. Therefore, the flange portion 90 f of the introduction channel forming plate 90 is positioned at the bottom of the introduction channel forming plate 90 .

The flange portion 90f of the introduction passage forming plate 90 is formed with an introduction portion communicating portion H2. Therefore, the introduction portion communication portion H2 is formed at the lowest portion of the introduction passage forming plate 90 . The introduction portion communication portion H2 is formed at a portion of the introduction passage forming plate 90 located below the axis L of the turbine wheel 13 extending in the horizontal direction in the vertical direction. The introduction portion communication portion H2 is a notch formed in a portion of the flange portion 90f of the introduction passage forming plate 90 . The introduction portion communication portion H2 penetrates the flange portion 90f in the thickness direction. The introduction portion communication portion H2 allows the introduction portion gap portion 92 and the inside of the upstream side exhaust pipe 94, which is a part of the exhaust passage 95, to communicate with each other. Therefore, the introduction portion communication portion H2 is a communication portion H that allows communication between the introduction portion gap portion 92 that is the gap portion G and the inside of the upstream side exhaust pipe 94 that is a part of the exhaust passage 95 . Therefore, the interior member 30b has a communicating portion H that communicates the gap portion G and the exhaust passage 95 with each other. The communicating portion H includes an introducing portion communicating portion H2 that allows the introducing portion gap portion 92 and the upstream exhaust pipe 94 to communicate with each other.

Next, the operation of the second embodiment will be described.
Exhaust gas flows into the introduction part gap 92, and heat is exchanged between the exhaust gas that has flowed into the introduction part gap 92 and the introduction part forming part 37, whereby the exhaust gas is cooled and contained in the exhaust gas. Condensed water W may be generated in the inlet gap portion 92 by condensing the water vapor. The condensed water W generated in this way flows downward in the vertical direction through the introduction section gap 92 along the inner peripheral surface 370 of the introduction section forming section 37 and the outer peripheral surface 900 of the tubular main body section 90a due to its own weight. Then, the condensed water W that has flowed to the bottom of the inlet gap 92 is discharged into the upstream exhaust pipe 94 through the inlet communication portion H2 as indicated by an arrow A1. The condensed water W discharged into the upstream side exhaust pipe 94 from the inlet space 92 through the inlet communication portion H2 flows through the upstream side exhaust pipe 94 together with the exhaust gas flowing inside the upstream side exhaust pipe 94. Also, since the condensed water W is evaporated by the heat of the exhaust gas, accumulation of the condensed water W in the introduction section gap 92 is suppressed.

The following effects can be obtained in the second embodiment.
(2-1) Even if the water vapor contained in the exhaust gas is condensed and the condensed water W is generated in the introduction section gap 92, the condensed water W is removed from the introduction section gap 92 via the introduction section communication section H2. It can be discharged to the inside of the side exhaust pipe 94 . The condensed water W discharged into the upstream side exhaust pipe 94 from the inlet space 92 through the inlet communication portion H2 is discharged into the upstream side exhaust pipe 94 together with the exhaust gas flowing inside the upstream side exhaust pipe 94. or evaporate due to the heat of the exhaust gas. Therefore, it is possible to prevent the condensed water W from accumulating in the introduction section gap 92 between the introduction section forming section 37 and the introduction channel forming plate 90 .

(2-2) The introduction portion communication portion H2 is formed at a portion of the introduction passage forming plate 90 located below the axis L of the turbine wheel 13 extending in the horizontal direction in the vertical direction. As a result, the condensed water W flowing vertically downward through the introduction section gap 92 due to its own weight is easily discharged from the introduction section gap 92 into the upstream side exhaust pipe 94 via the introduction section communication portion H2. Therefore, the condensed water W generated in the introduction part gap 92 can be efficiently discharged from the introduction part gap 92 to the upstream side exhaust pipe 94 via the introduction part communication part H2. Accumulation of W can be easily suppressed.

(2-3) Since the condensed water W generated in the introduction section gap 92 flows vertically downward through the introduction section gap 92 due to its own weight, the condensed water W generated in the introduction section gap 92 is It tends to accumulate at the bottom of the gap 92 . At this time, since the introduction portion communication portion H2 is formed in the flange portion 90f positioned at the lowest portion of the introduction passage forming plate 90, the condensed water W accumulated in the lowermost portion of the introduction portion gap portion 92 flows into the introduction portion gap. It is easy to discharge from the portion 92 to the upstream side exhaust pipe 94 via the introduction portion communication portion H2. Therefore, the condensed water W generated in the introduction part gap 92 can be efficiently discharged from the introduction part gap 92 to the upstream side exhaust pipe 94 via the introduction part communication part H2. Accumulation of W can be easily suppressed.

It should be noted that each of the above-described embodiments can be implemented with the following modifications. The above embodiments and the following modifications can be combined with each other within a technically consistent range.

O As shown in FIG. 6, the annular plate 70 may have an annular plate communication portion H3 that communicates the annular gap portion 74 and the turbine scroll passage 35 with each other. The annular plate communicating portion H3 is formed in a portion of the annular plate 70 radially inside the outer peripheral edge 71 sandwiched between the end surface 31d of the peripheral wall 31b of the housing body portion 31 and the end surface 380 of the projecting portion 38d. The annular plate communicating portion H3 is a through hole that penetrates the annular plate 70 in the thickness direction. The annular plate communicating portion H3 faces the scroll communicating portion H1 in the axial direction of the turbine wheel 13 . Therefore, the annular plate communicating portion H3 is formed at a portion of the annular plate 70 positioned below the axis L of the turbine wheel 13 extending in the horizontal direction in the vertical direction. The annular plate communicating portion H3 is a communicating portion H that allows the annular gap portion 74, which is the gap portion G, and the turbine scroll passage 35, which is a part of the exhaust passage 95, to communicate with each other. Therefore, the communicating portion H includes an annular plate communicating portion H3 that allows the annular gap portion 74 and the turbine scroll passage 35 to communicate with each other.

Exhaust gas flows into an annular gap 74 formed between the closing member 38 and the annular plate 70, and heat is exchanged between the exhaust gas flowing into the annular gap 74 and the closing member 38, whereby the exhaust gas is discharged. Water vapor contained in the exhaust gas may be cooled and condensed to form condensed water W in the annular gap 74 . Even in this case, the condensed water W can be discharged from the annular gap portion 74 to the turbine scroll passage 35 via the annular plate communicating portion H3. The condensed water W discharged from the annular gap portion 74 to the turbine scroll passage 35 through the annular plate communication portion H3 flows through the turbine scroll passage 35 together with the exhaust gas flowing through the turbine scroll passage 35, or heats the exhaust gas. evaporate by Therefore, in addition to suppressing the accumulation of condensed water W in the scroll gap 65 between the housing main body 31 and the scroll passage forming plate 60, the annular gap between the closing member 38 and the annular plate 70 is prevented. Accumulation of the condensed water W in the gap 74 can also be suppressed.

(circle) in each said embodiment, the exterior member 30a may not be made by casting, and the interior member 30b may not be made by sheet metal. In short, as long as the turbine housing 30 has a double structure having the exterior member 30a and the interior member 30b, the materials of the exterior member 30a and the interior member 30b may be appropriately changed.

(circle) in 1st Embodiment and embodiment shown in FIG. 6, the scroll communication part H1 may not be a notch, but may be a through-hole, for example.
(circle) in 2nd Embodiment, the introduction|transduction part communication part H2 may not be a notch, and may be a through-hole, for example.

O In the embodiment shown in FIG. 6, the turbine housing 30 may have a configuration in which the scroll passage forming plate 60 is not provided with the scroll communicating portion H1. Even in this case, the condensed water W can be discharged from the annular gap portion 74 to the turbine scroll passage 35 via the annular plate communicating portion H3. The condensed water W discharged from the annular gap portion 74 to the turbine scroll passage 35 through the annular plate communication portion H3 flows through the turbine scroll passage 35 together with the exhaust gas flowing through the turbine scroll passage 35, or heats the exhaust gas. evaporate by Therefore, it is possible to prevent the condensed water W from accumulating in the annular gap 74 between the closing member 38 and the annular plate 70 .

(circle) in 1st Embodiment, the structure which does not have the clearance reduction part R may be sufficient as the scroll clearance part 65. FIG. For example, the distance between the inner peripheral surface 310 of the peripheral wall 31b of the housing main body 31 and the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll passage forming plate 60 is always constant in the circumferential direction of the peripheral wall 31b of the housing main body 31. There may be. Also, the distance between the inner peripheral surface 310 of the peripheral wall 31b of the housing main body 31 and the outer peripheral surface 61a of the outer peripheral wall 61 of the scroll passage forming plate 60 may gradually increase as it approaches the scroll communicating portion H1.

(circle) in 1st Embodiment, the scroll communication part H1 does not need to be formed in the lowest part in the scroll flow-path formation plate 60. FIG. Even in this case, for example, the scroll communicating portion H1 is preferably formed at a portion of the scroll passage forming plate 60 located vertically below the axis L of the turbine wheel 13 extending in the horizontal direction. .

○ In the first embodiment, the scroll communicating portion H1 may be formed, for example, in a portion of the scroll passage forming plate 60 located vertically above the axis L of the horizontally extending turbine wheel 13 . The point is that the condensed water W generated in the scroll gap portion 65 can be discharged to the turbine scroll passage 35 via the scroll communication portion H1. It is not limited.

O In the second embodiment, the inlet communicating portion H2 may not be formed in the flange portion 90f positioned at the bottom of the inlet passage forming plate 90. For example, the inlet passage forming plate 90 may The introduction portion communicating portion H2 may be formed so as to penetrate the main body portion 90a in the thickness direction. In this case, the introduction part communication part H2 allows the introduction part gap part 92 and the introduction flow path 37a, which is a part of the exhaust passage 95, to communicate with each other. Then, the condensed water W generated in the introduction section gap 92 is discharged to the introduction passage 37a through the introduction section communication section H2.

REFERENCE SIGNS LIST 13 Turbine wheel 30 Turbine housing 30a Exterior member 30b Interior member 31 Housing body 31a Bottom wall 31b Peripheral wall 35 Turbine scroll flow path as a scroll flow path 37a Introduction Flow path 38 Closing member 60 Scroll flow path forming plate 61a Peripheral surface 65 Scroll gap 70 Annular plate 74 Annular gap 90 Introductory flow path forming plate 92 Introductory portion Gap part 95... Exhaust passage 310... Inner peripheral surface E... Engine G... Gap part H... Communication part H1... Scroll communication part H2... Introduction part communication part H3... Annular plate communication part R... Gap reduction part, W: condensed water.

Claims (4)

an interior member that forms at least an inner wall of a spiral scroll flow passage that is a part of an exhaust passage through which exhaust gas discharged from the engine flows and surrounds the turbine wheel;
and an exterior member that accommodates the interior member via a gap, wherein
The interior member has a communicating portion that communicates the void portion and the exhaust passage,
The communicating portion is formed only vertically below an axis of the turbine wheel extending horizontally in the interior member,
The exterior member is
a bottomed cylindrical housing main body having a plate-like bottom wall and a cylindrical peripheral wall erected from an outer peripheral portion of the bottom wall;
a closing member that closes the opening of the peripheral wall of the housing main body,
The interior member is
a scroll passage forming plate forming an inner wall of the scroll passage on the side of the housing main body,
the gap includes a scroll gap formed between the housing main body and the scroll passage forming plate;
The turbine housing , wherein the communicating portion includes a scroll communicating portion that communicates between the scroll gap portion and the scroll passage . 2. The turbine housing according to claim 1 , wherein the scroll communicating portion is formed at the lowest portion of the scroll passage forming plate. an interior member that forms at least an inner wall of a spiral scroll flow passage that is a part of an exhaust passage through which exhaust gas discharged from the engine flows and surrounds the turbine wheel;
and an exterior member that accommodates the interior member via a gap, wherein
The interior member has a communicating portion that communicates the void portion and the exhaust passage,
The exterior member is
a bottomed cylindrical housing main body having a plate-like bottom wall and a cylindrical peripheral wall erected from an outer peripheral portion of the bottom wall;
a closing member that closes the opening of the peripheral wall of the housing main body,
The interior member is
a scroll passage forming plate forming an inner wall of the scroll passage on the side of the housing main body,
the gap includes a scroll gap formed between the housing main body and the scroll passage forming plate;
the communicating portion includes a scroll communicating portion that communicates the scroll gap portion and the scroll flow path;
The scroll communicating portion is formed at the lowest portion of the scroll passage forming plate,
The scroll clearance portion has a clearance reduction portion in which the distance between the inner peripheral surface of the housing main body portion and the outer peripheral surface of the scroll passage forming plate gradually decreases as the distance between the inner peripheral surface of the housing body portion and the outer peripheral surface of the scroll passage forming plate approaches the scroll communication portion. A turbine housing, characterized in that: The interior member further has an annular plate that forms an inner wall of the scroll passage on the closing member side,
the gap includes an annular gap formed between the closing member and the annular plate;
The turbine housing according to any one of claims 1 to 3 , wherein the communicating portion includes an annular plate communicating portion that communicates between the annular gap portion and the scroll passage.