JP2018173056A - Exhaust turbo supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhaust turbo supercharger whose tongue part is excellent in heat radiation.MEANS: A cooling water jacket 31 encircling a scroll chamber 8 and an inlet passage 9 is divided into upper and lower jackets 33, 34 by left and right partition walls 32a, 32b. The upper and lower jackets 33, 34 are communicated with each other via front and rear communication parts. Cooling water flows from the lower jacket 34 to the upper jacket 33. Part of the partition wall 32b is arranged beside a tongue part 46. The partition wall 32b is formed with a communication hole 44 opened to the upper and lower jackets 33, 34. The existence of the communication hole 44 remarkably increases the heat radiation of the partition wall 32b, thus highly promoting heat to be radiated from the tongue part 46 to the cooling water.SELECTED DRAWING: Figure 9

Description

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

  The exhaust turbocharger has a turbine housing in which a turbine is rotatably arranged, and a spiral shape with a distance from the rotation axis becoming smaller from the start end to the end is formed on the outer periphery of the turbine chamber. A scroll chamber is formed, and an inlet passage communicates with the start end of the scroll chamber. The end portion of the scroll chamber is located in the vicinity of the end portion of the inlet passage, but due to the scroll chamber having a spiral shape, between the end portion of the inlet passage and the end portion of the scroll chamber. The part is a tongue that decreases in thickness in the flow direction of the exhaust gas.

  In the exhaust turbocharger, since the tongue of the turbine housing is the part most strongly affected by heat, it is considered to reduce heat damage. As an example, Patent Document 1 discloses that when a cooling water jacket is formed on one side of the scroll chamber, a rib is provided in a portion of the cooling water jacket located beside the tongue.

  On the other hand, Patent Document 2 discloses that when the turbine housing is made of aluminum, the tongue is made of steel and cast into the turbine housing. Patent Document 2 also discloses forming a cooling water jacket so as to surround the scroll chamber.

Japanese Patent Laying-Open No. 2006-173068 JP 2016-47287 A

  Making the turbine housing water-cooled is beneficial to the entire turbine housing, and as disclosed in Patent Document 2, by providing a cooling water jacket, the turbine housing can be made aluminum to reduce the weight. Become. However, since the tongue is susceptible to heat damage based on its structure, countermeasures against heat damage are particularly required.

  However, as described in Patent Document 2, the measures for casting with the tongue made of steel are a problem that takes a lot of labor for manufacturing, a problem that accuracy may be lowered due to variation in dimensions, or a heat of steel and aluminum. There is a concern that the tongue may be loose due to a difference in expansion rate. On the other hand, it can be said that the countermeasure of Patent Document 1 can effectively use the cooling water jacket because the heat received by the tongue is radiated to the cooling water through the ribs.

  The present invention has been made in view of such a current situation, and is intended to improve the cooling performance of the tongue by further utilizing cooling water while providing a cooling water jacket as in Patent Document 1. is there.

  The exhaust turbocharger of the present invention includes a turbine chamber in which a turbine is rotatably arranged, a scroll chamber that surrounds the turbine chamber, and an inlet passage that feeds exhaust gas into the scroll chamber. A portion between the end portion of the inlet passage and the turbine chamber has a basic configuration in which a tongue portion whose thickness decreases in the exhaust gas flow direction.

  The housing is formed with a cooling water jacket positioned on at least one of the left and right sides of the scroll chamber as viewed from the axial direction of the inlet passage, and the cooling water jacket is substantially lateral to the tongue. A partition hole having a portion positioned at the top and bottom is divided into upper and lower portions, and a communication hole through which cooling water and air can pass is formed in a portion of the partition wall positioned substantially beside the tongue.

  In the present invention, the material of the turbine housing is not limited, but if it is made of a light metal such as aluminum, the weight can be reduced and the water-cooled merit can be greatly enjoyed. Although the cooling water jacket can be formed only on one side of the scroll chamber as in Patent Document 1, it is preferable to form the cooling water jacket so as to entirely surround the scroll chamber. Therefore, it is preferable that cooling water jackets are formed on both the left and right sides of the scroll chamber, the left and right cooling water jackets are partitioned vertically by the partition walls, and communication holes are formed in the left and right partition walls, respectively.

  In the present invention, since the cooling water jacket is vertically separated via the left and right partition walls, the portion located outside and the portion located inside the cooling water jacket are connected by the partition walls. For this reason, even if the scroll chamber is entirely surrounded by the cooling water jacket, the inner portion surrounded by the cooling water jacket is not easily deformed, and high rigidity can be secured. Moreover, since the partition functions also as a heat radiating portion like the rib of Patent Document 1, it can contribute to the improvement of the cooling performance by suppressing the accumulation of heat.

  And since there is a communication hole in the partition wall, the cooling water flows from the lower jacket to the upper jacket or from the upper jacket to the lower jacket through this communication hole, so that heat is exchanged from the partition wall to the cooling water. The amount is remarkably high, and as a result, heat radiation from the tongue to the cooling water is also promoted. As a result, it is possible to prevent the tongue from being excessively heated and to ensure high reliability.

  In addition, since the communication hole can also function as an air vent hole, air bubbles mixed in the cooling water stay on the lower surface of the partition wall and heat dissipation is reduced, or bubbles generated by boiling the cooling water are generated in the partition wall. There is no such thing as staying on the lower surface of the metal and reducing heat dissipation. According to this, high reliability can be ensured.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall view of an exhaust turbocharger according to an embodiment, where (A) is a perspective view seen from the direction of the intake inlet, and (B) is a perspective view seen from the inlet direction of the exhaust gas. (A) is a top view of an exhaust turbocharger, and is a front view of (B). It is the III-III sectional view taken on the line of FIG. (A) is a plan view of the turbine housing, (B) is a plan view in which the cooling water jacket is indicated by a solid line and the outer shape of the turbine housing is indicated by a one-dot chain line, and (C) is a turbine in which the exhaust gas passage is indicated by a solid line. It is the top view which displayed the external shape of the housing with the dashed-dotted line. (A) is the front view of a turbine housing, (B) is the front view which displayed the cooling water jacket with the continuous line, and displayed the external shape of the turbine housing with the dashed-dotted line. (A) is a right side view of the turbine housing, and (B) is a right side view in which a cooling water jacket is indicated by a solid line and an outer shape of the turbine housing is indicated by a one-dot chain line. (A) is a bottom view of the turbine housing, (B) is a left sectional view taken along the line VIIB-VIIB of FIG. 4 (A), and (C) is a left side view of the cooling water jacket. 4A is a sectional view taken along the line VIIIA-VIIIA in FIGS. 4A and 5A, and FIG. 5B is a sectional view taken along the line BB in FIG. 5A and is a sectional view taken along the line VIIIB-VIIIB in FIG. , (C) is a schematic sectional view taken along the line VIIIC-VIIIC of FIGS. 4 (A), 6 (A) and 7 (B). 4A is a cross-sectional view taken along the line IX-IX in FIGS. 4A and 7B, and FIG. 6B is a cross-sectional view taken along the line IXB-IXB in FIGS. 6A and 8A.

(1). Outline Next, an embodiment of the present invention will be described with reference to the drawings. First, an outline will be described with reference to FIGS. In this embodiment, the front / rear, left / right, and upper / lower terms are used to clarify the direction. The longitudinal direction of the rotation axis is the left / right direction, and the direction orthogonal to the exhaust side of the cylinder head is the front / rear direction. The direction facing the cylinder head is the front. The vertical direction is the vertical direction. As a precaution, the directions are clearly shown in FIGS.

  As shown in FIG. 3, the exhaust turbocharger includes a blade-type turbine 1 and a compressor blade 2, both of which are fixed to one end and the other end of a horizontal rotation shaft 3. . The exhaust turbocharger has a turbine housing 4 and a compressor housing 5 and an intermediate housing 6 positioned between the turbine housing 4 and the turbine housing 4. The turbine housing 4 and the intermediate housing 6 are cast as aluminum. It is manufactured integrally. The compressor housing 5 is an aluminum die-cast product or cast product.

  The turbine housing 4 is formed with a turbine chamber 7 in which the turbine 1 is rotatably arranged, and a turbine-side scroll chamber 8 communicating with the outer periphery of the turbine chamber 7. The turbine-side scroll chamber 8 has a spiral shape in which the distance from the rotation axis of the turbine 1 gradually decreases from the start end to the end, and the inlet passage shown in FIG. 9 communicates.

  Accordingly, the turbine housing 4 has a circular portion 4 a in which the turbine-side scroll chamber 8 is formed, and an inlet cylinder portion 4 b in which the inlet passage 9 is formed, and protrudes on the opposite side to the intermediate housing 6. The side projecting portion 4c is formed so as to be integrally connected to the circular portion 4a and the inlet tube portion 4b. At the rear end of the inlet cylinder 4b, an inlet flange 12 is formed that is fixed to the cylinder head (or an exhaust manifold assembly) with bolts.

  As can be understood from FIG. 3, the side projecting portion 4 c is formed with an outlet passage 13 through which exhaust gas discharged from the turbine chamber 7 flows and a wastegate passage 14 that connects the inlet passage 9 and the outlet passage 13. The wastegate passage 14 is opened and closed by a pivotable wastegate valve 15. A shroud piece 13 a for constituting the inner peripheral portion of the turbine side scroll chamber 8 is attached to the outlet passage 13. The wastegate valve 15 is driven by a diaphragm actuator 16 shown in FIG. The actuator 16 has a rod 17, and when the rod 17 moves back and forth, the wastegate valve 15 rotates about the axis of the support shaft 19 via the outer link 18, the support shaft 19, and the inner link 20. .

  An outlet side flange 21 is formed on the side projecting portion 4c, and although not shown, a catalyst case is fixed to the outlet side flange 21 (an exhaust pipe may be fixed). The outlet hole 13b through which the exhaust gas is discharged opens obliquely downward.

  As shown in FIG. 3, the compressor housing 5 is formed with an intake inlet 22 and a compressor side scroll chamber 23 located outside the compressor blade 2, and the intake air pressurized in the compressor side scroll chamber 23 is The air is discharged from the discharge port 24 to the intake system. The compressor housing 5 is connected to the intermediate housing 6 via a C-shaped or split ring 25.

  The intermediate housing 6 is formed with a bearing portion 27 that rotatably holds the rotating shaft 3 via a floating metal 26. An oil supply hole 28 that opens upward and an oil discharge hole 29 that opens downward are formed in the bearing portion 27. Since the seal structure of the rotating shaft 3 is not related to the present invention, the description thereof is omitted.

(2) Cooling structure of turbine housing The turbine housing 4 is formed with a cooling water jacket through which cooling water flows. This point will be described with reference to FIG. As shown in FIGS. 7C and 8, the cooling water jacket 31 has an upper jacket 33 and a lower jacket 34 that are divided into upper and lower portions via left and right partition walls 32 a and 32 b, and these upper and lower jackets 33. , 34 communicate with each other by one front communication portion 35 and two rear communication portions 36 on the left and right. The front partition wall 32a and the rear partition wall 32b are roughly divided into front and rear sides with the scroll chamber 8 interposed therebetween.

  A cooling water inlet 37 communicates with the lower jacket 34, and a cooling water outlet 38 communicates with the upper jacket 33. The cooling water inlet 37 and the cooling water outlet 38 are formed in the boss portion. As shown in FIGS. 8 and 9A, the cooling water inlet 37 and the cooling water outlet 38 are connected via the bore joint cylinders 37a and 38a. Connected to the hose.

  Since the circular portion 4a and the inlet cylinder portion 4b are connected to each other by left and right partition walls 32a and 32b, the inside through which the exhaust gas flows is stably held, and high rigidity is ensured as a whole. Further, since the communication portions 35 and 36 are separated into front and rear, the cooling water flows through the entire upper and lower jackets 33 and 34 and is discharged from the cooling water outlet 38. Therefore, the entire turbine housing 4 can be cooled as evenly as possible to greatly suppress the occurrence of thermal strain.

  As shown in FIGS. 3, 5, 7 (A) and (B), the side projecting portion 4 c has a mountain shape protruding above the circular portion 4 a and the inlet tube portion 4 b, and the exit is located at the highest portion. A boss 39 is formed, and a cooling water outlet 38 is formed in the boss 39. Therefore, the upper jacket 33 has a funnel shape that is narrowed upward in a side view and a front view, and the cooling water sent from below is collected at the cooling water outlet 38 without stagnation in the middle. It is surely discharged. For example, in FIG. 6B, the upward projecting portion of the upper jacket 33 is indicated by reference numeral 33a.

  Further, for example, as clearly shown in FIG. 5, the cooling water inlet 37 of the cooling water jacket 31 is located directly below the turbine chamber 7 and has a cylindrical shape, while the cooling water outlet 38 is formed from the scroll chamber 8. Are also biased toward the exit passage 13 and the wastegate passage 14, and both are separated (offset) in the left-right direction. Further, both the upper and lower cooling water jackets 33 and 34 have a much larger volume on the outlet passage 13 and the wastegate passage 14 side than on the intermediate housing 6 side. For this reason, the site | part (especially site | part enclosed by the exhaust-gas channel | path) exposed to high temperature and being easily damaged by heat is cooled strongly, and generation | occurrence | production of a thermal strain can be suppressed significantly.

  The communication holes 35 and 36 are formed by fitting a screw-type plug 41 into the cavity 40 that opens outward. That is, by screwing the plug 41 partway into the cavity 40, a part of the cavity 40 is formed with the communication holes 35 and 36.

  As can be understood from FIGS. 4B and 8A, the circular portion 4a is provided with auxiliary ribs 42 and 43 that bisect the upper jacket 33 and the lower jacket 34 in the left and right directions. For this reason, the rigidity of the holding portion of the turbine 1 is ensured, and accurate rotation of the turbine 1 can be ensured. Further, since the ribs 42 and 43 can also maintain a rectifying function for dividing the water flow into left and right, it is possible to contribute to the smooth flow of the cooling water. Furthermore, since the ribs 42 and 43 also exhibit a function of heat dissipation, there is an advantage that heat accumulation can be suppressed.

  As shown in FIG. 7 (B), the inlet cylinder 4b is inclined so that its height increases slightly from the rear end toward the front end. For this reason, as shown in FIG.7 (C), the part located in the location of the inlet cylinder part 4b among the cooling water jacket 31 is also inclined slightly in side view so that it may become high toward this side. Corresponding to the form of the cooling water jacket 31, the rear partition wall 32b is inclined so as to rise once, then back in a horizontal posture, and then lower toward the back. The upper surface of this is formed in a mountain shape in a side view.

  Therefore, in order to reliably prevent air bubbles from collecting at the upper end portion of the lower jacket 34, a communication hole 44 is formed in the high portion of the rear partition wall 32b as shown in FIG. 9A. For this reason, even if the cooling water contains bubbles or the cooling water boils and bubbles are generated, the bubbles can be quickly removed and higher cooling performance can be secured. Since the communication hole 44 is formed by drilling, the turbine housing 4 has a drill hole 45 concentric with the communication hole 44, but the drill hole 45 is closed by a plug (not shown).

  As shown in FIG. 8, since the turbine side scroll chamber 8 is spiral, the portion of the turbine side scroll chamber 8 sandwiched between the end portion of the inlet passage 9 has a thickness toward the tip. Is a thinned tongue 46. For this reason, the tongue 46 is exposed to the harshest thermal environment in the turbine housing 4, but in this embodiment, a part of the rear partition wall 32b is located substantially beside the tongue 46, and the rear partition wall 32b A communication hole 44 is vacant at a portion located beside the tongue 46. The tongue portion 46 and the rear partition wall 32b may have some height differences, but preferably overlap at least partially in a side view.

  And since a cooling water flows through the communicating hole 44, the heat exchange from the rear partition 32b to a cooling water is accelerated | stimulated remarkably, Therefore The heat of the tongue part 46 is also thermally radiated to a cooling water via the rear partition 32b. As a result, it is possible to prevent the tongue portion 46 from being excessively heated and to eliminate problems such as melting damage.

  As shown in FIG. 9A, the inlet passage 9 and the wastegate passage 14 are arranged side by side, and one side of the rear partition wall 32b is located between them, but the rear partition wall 32b communicates with the air vent hole. If the hole 44 is formed, heat transfer from the portion of the wastegate passage 14 can be suppressed, which is more useful as a protection means for the tongue 46. A plurality of communication holes 44 may be provided in one rear partition wall 32b. In the left and right rear partition walls 32b, the number and the inner diameters of the communication holes 44 can be varied.

  The embodiment of the present invention has been described above, but the present invention can be embodied in various ways. For example, the form of the cooling water jacket can be appropriately set according to the shape of the turbine housing and the like. The intermediate housing and the turbine housing may be separate.

  The present invention can actually be embodied in an exhaust turbocharger. Therefore, it can be used industrially.

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Turbine 3 Compressor blade 4 Turbine housing 4a Circular part 4b Inlet cylinder part 4c Side overhang part 8 Turbine side scroll chamber 9 Inlet passage 31 Cooling water jacket 32a, 32b Partition 33 Upper jacket 34 Lower jacket 35, 36 Communication part 37 Cooling water inlet 39 Cooling water outlet 44 Communication hole 46 Tongue

Japanese Patent Laying-Open No. 2006-173068 Japanese Patent Laid-Open No. 2006-75287

Claims (1)

The housing includes a turbine chamber in which a turbine is rotatably disposed, a scroll chamber that surrounds the turbine chamber, and an inlet passage that sends exhaust gas into the scroll chamber, and a terminal portion of the inlet passage and the turbine chamber, The portion between is a tongue portion whose thickness decreases in the exhaust gas flow direction,
The housing is formed with a cooling water jacket positioned on at least one of the left and right sides of the scroll chamber when viewed from the axial direction of the inlet passage, and the cooling water jacket is positioned substantially beside the tongue. Are separated vertically by a partition wall having a portion formed therein, and a communication hole through which cooling water and air can pass is formed in a portion of the partition wall that is positioned substantially beside the tongue,
Exhaust turbocharger.

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