Exhaust manifold with turbine connector having turbine foot

Abstract

A turbine connector (40) in an engine exhaust manifold (30) includes a turbine leg (54) attached to an inlet exhaust conduit (42, 46). The turbine leg (54) has an outer peripheral edge (72) defining a trapezoidal shape and an inner peripheral edge (86, 90) forming exhaust outlets (88, 92) from the inlet exhaust conduit (42, 46). The inner peripheral edge (86, 90) has a peripheral curvature with a maximum change in magnitude of curvature on a web (94) extending between the exhaust outlets (88, 92) and together form an hourglass web profile in a turbine mounting plane defined by the turbine leg (54).

Description

Technical Field

[0001] This disclosure generally relates to a turbine connector for an engine exhaust manifold, and more specifically to a turbine mount shaped to resist cracking, facilitate installation, and optimize the exhaust flow of the turbine in the exhaust system. Background Technology

[0002] Many modern internal combustion engines employ one or more turbochargers to extract energy from engine exhaust and use that energy to increase intake air pressure. In a typical configuration, the turbocharger is mounted to the engine exhaust manifold, which collects exhaust streams from the engine's combustion cylinders and supplies the combined exhaust streams to the inlet of a turbine in the turbocharger. The exhaust streams through the turbine impact the turbine blades, causing the turbine to rotate. The turbine shaft extends to a compressor impeller, which is fluidly positioned within the intake stream for the engine's intake air, or sometimes within the intake air and fumigated fuel and / or recirculated exhaust. The rotation of the compressor impeller increases the intake air pressure, enabling the associated internal combustion engine to operate with increased power, increased power density, and / or improved efficiency based on the extraction of exhaust energy that would otherwise be wasted.

[0003] The typical operating environment of a turbocharger is extremely harsh, as the turbocharger itself and associated components may be subjected to extreme temperatures, temperature fluctuations, high absolute pressures, corrosive fluids, and overall dynamic mechanical environments. For these reasons, turbochargers, exhaust manifolds, and associated equipment are typically constructed to be quite robust. As mentioned above, the engine exhaust manifold typically collects exhaust gases from multiple cylinders and provides a combined exhaust flow feed to the turbocharger. The desire to limit interruptions, disturbances, or so-called "crosstalk" in the exhaust flow caused by dynamic and rapidly changing pressures from cylinder to cylinder has led many manufacturers to design the exhaust feed to the turbine in a manner where the exhaust flow from some cylinders is separated from the exhaust flow from other cylinders, at least until the point where the exhaust enters the turbine housing. This configuration requires a partition wall or web separating the exhaust flow at the point where the exhaust flow leaves the exhaust manifold and enters the turbine housing. The relatively thin metal partition walls in the exhaust manifold casting may experience stress and potential thermal fatigue earlier than expected during the engine's service life. A known exhaust system with a low-stress exhaust manifold flange is described in U.S. Patent No. 6,892,532 to Bruce et al. Bruce et al. proposed an exhaust system in which an exhaust flange is connected to an exhaust manifold, and a turbocharger is connected to the exhaust flange. The turbocharger has an exhaust inlet flange connected to the exhaust flange. The exhaust ports of the exhaust flange all have a generally triangular cross-sectional configuration. Summary of the Invention

[0004] In one aspect, a turbine connector for an engine exhaust manifold includes a first inlet exhaust pipe and a second inlet exhaust pipe. The turbine connector also includes a turbine mount attached to the first and second inlet exhaust pipes. The turbine mount includes an engine-facing side and a turbine mounting side opposite the engine-facing side, comprising a platform defining a turbine mounting plane. The turbine mount also includes an outer edge having a long peripheral base, a short peripheral base, and a first peripheral leg and a second peripheral leg extending at an angle between the long and short peripheral bases. The turbine mount further includes: a first inner edge forming a first exhaust outlet from the first inlet exhaust pipe that opens in the platform; a second inner edge forming a second exhaust outlet from the second inlet exhaust pipe that opens in the platform; and a web extending between the first and second exhaust outlets. The first and second inner edges each have varying peripheral curvature and together form an hourglass web profile in the turbine mounting plane, the varying peripheral curvature being maximized at a finite curvature magnitude on the web.

[0005] On the other hand, the engine exhaust manifold includes a first exhaust pipe configured to be fluidly connected to a first group of engine cylinders and a second exhaust pipe configured to be fluidly connected to a second group of engine cylinders. The engine exhaust manifold also includes a turbine connector coupled to the first and second exhaust pipes and including a turbine foot. The turbine foot has an outer peripheral edge defining a trapezoidal shape, a first inner peripheral edge, and a second inner peripheral edge. The first inner peripheral edge forms an exhaust feed from the first group of engine cylinders to a first exhaust outlet of the turbine, and the second inner peripheral edge forms an exhaust feed from the second group of engine cylinders to a second exhaust outlet of the turbine. The turbine foot also includes a web extending between the first and second exhaust outlets. The first and second exhaust outlets are mirror images of each other and each has a varying inner curvature, the varying inner curvature being maximized at a finite curvature magnitude on the web.

[0006] In another aspect, a turbine connector for an engine exhaust manifold includes a first inlet exhaust pipe and a second inlet exhaust pipe. The turbine connector also includes a turbine mount attached to the first and second inlet exhaust pipes, and having an engine-facing side and a turbine mounting side opposite the engine-facing side, comprising a platform defining a turbine mounting plane. The turbine mount also includes an outer edge defining a trapezoidal shape and having a plurality of bolt holes extending between the engine-facing side and the turbine mounting side and arranged in a trapezoidal pattern conforming to the trapezoidal shape. The turbine mount also includes: a first inner edge forming a first exhaust outlet from the first inlet exhaust pipe opening in the platform; a second inner edge forming a second exhaust outlet from the second inlet exhaust pipe opening in the platform; and a web extending between the first and second exhaust outlets. The first and second inner edges each have varying peripheral curvatures and together form an hourglass web profile in the turbine mounting plane. Attached Figure Description

[0007] Figure 1 This is a schematic end view of an internal combustion engine system according to one embodiment;

[0008] Figure 2 This is a schematic diagram of an engine exhaust manifold according to one embodiment;

[0009] Figure 3 This is a schematic diagram of a portion of a turbine connector for an engine exhaust manifold according to one embodiment; and

[0010] Figure 4 This is a front view of a turbine support leg according to one embodiment. Detailed Implementation

[0011] Reference Figure 1 An internal combustion engine system 10 according to one embodiment is illustrated. The internal combustion engine system 10 includes a cylinder block 12 and an engine cylinder head 14 mounted to the cylinder block 12. An engine cylinder or combustion cylinder 16 is formed in the cylinder block 12, and a piston 18 is positioned within the combustion cylinder 16 and is movable in a conventional manner between a top dead center (TDC) position and a bottom dead center (BDC) position to rotate a crankshaft. The combustion cylinder 16 can be one of a plurality of combustion cylinders in any suitably arranged configuration, such as a V-pattern, an inline pattern, or another. The internal combustion engine system 10 can include a four-stroke, direct-injection, liquid-fuel compression-ignition engine; however, this disclosure is not limited thereto, and the internal combustion engine system 10 can be a spark-ignition, gas-fueled, gasoline, or dual-fuel engine system operating in a two-stroke cycle, or otherwise varied.

[0012] The internal combustion engine system 10 also includes an exhaust system 20, which includes a turbocharger 22 having a turbine 24 and a turbine inlet 26. The exhaust system 20 also includes an engine exhaust manifold 30 configured to collect exhaust gases from a plurality of combustion cylinders formed in the cylinder block 12. In a practical embodiment, the exhaust system 20 may also include an aftertreatment device (not shown) configured to receive the exhaust flow from the turbine 24 and treat the exhaust in a generally conventional manner to reduce certain emissions. An intake manifold is shown at 28 and is configured to receive intake airflow from the compressor (not shown) of the turbocharger 22 to the respective combustion cylinders.

[0013] Still referencing Figure 2 The engine exhaust manifold 30 may include a body 41 having a first exhaust pipe 32 and a second exhaust pipe 34. The first exhaust pipe 32 may receive exhaust from a first group of cylinders in the cylinder block 12, such as three or four cylinders, and the second exhaust pipe 34 may receive exhaust from a second group of cylinders in the cylinder block 12, such as three or four cylinders. The body 41 may be a single-piece casting, but alternatively may include multiple parts such as those attached together by welding. The engine exhaust manifold 30 also includes a turbine connector 40 having a first inlet exhaust pipe 42 forming the first exhaust passage 44 and fluidly connected to the first exhaust pipe 32. The turbine connector 40 also includes a second inlet exhaust pipe 46 forming the second exhaust passage 48 and fluidly connected to the second inlet exhaust pipe 34.

[0014] exist Figure 2 In the illustration, a plurality of pins 64 are attached to a first exhaust pipe 32 and / or a first inlet exhaust pipe 42, and a second plurality of pins 68 are attached to a second exhaust pipe 34 and / or a second inlet exhaust pipe 46. The total number of pins may correspond to the total number of combustion cylinders formed in the cylinder block 12. Bolt holes 66 are formed in the pins 64, and bolt holes 70 are formed in the pins 68, for bolting to the cylinder block 12. Additional bolt holes, typically positioned opposite to the illustrated bolt holes, may be provided in the respective pins. Figure 2 These bolt holes are not visible in the diagram. Similarly, as... Figure 2As shown, the first accessory 50 connects the first exhaust pipe 32 to the first inlet exhaust pipe 42, and the second accessory 52 connects the second exhaust pipe 34 to the second inlet exhaust pipe 46. It will be recalled that the engine exhaust manifold 30 may be a single-piece unit, wherein multiple attachments and accessories may or may not be part of the design. Exhaust inlets 36 and 38 are formed in the respective exhaust pipes and / or exhaust passages to feed exhaust gas from the engine cylinders into exhaust pipes 32 and 34 and into the respective exhaust passages 44 and 48.

[0015] The turbine connector 40 also includes a turbine mount 54 attached to a first inlet exhaust pipe 42 and a second inlet exhaust pipe 46. The turbine mount 54 includes an engine-facing side 56 and a turbine mounting side 58 opposite the engine-facing side 56, which includes a platform 60 defining a turbine mounting plane 62. In a practical embodiment, when the turbocharger 22 is installed for use in the internal combustion engine system 10, a gasket, one or more metal seals, or similar elements are clamped between the turbine mount 54 and the turbocharger 22.

[0016] The turbine support 54 also includes a continuous outer peripheral edge 72 (hereinafter referred to as "outer edge 72"). The outer edge 72 has a long peripheral base 74, a short peripheral base 76, and a first peripheral leg 78 and a second peripheral leg 80, each extending at an angle between the long peripheral base 74 and the short peripheral base 76. It can be seen that, in the illustrated embodiment, the long peripheral base 74, the short peripheral base 76, the first peripheral leg 78, and the second peripheral leg 80 together define a trapezoidal shape. Also in the illustrated embodiment, this trapezoidal shape is an isosceles trapezoid. A trapezoidal shape, or other shapes where the peripheral legs extend at an angle between the long and short bases, can provide optimized size, platform area, and flow area for exhaust, as discussed further herein, and can facilitate the assembly operation of the internal combustion engine system 10. Figure 2 Obstacles 84 are also depicted on the opposite left and right sides of the turbine foot 54. During the assembly or maintenance of the exhaust system 20 in the internal combustion engine system 10, certain components, including housing components, pipes, electrical components, temperature management components, or various other components, may be installed or to be installed in a manner resembling other shapes of the turbine foot, such as square, rectangular, or curved shapes, which may physically interfere with or nearly physically interfere with such obstacles, or otherwise complicate or slow down the assembly. The disclosed turbine foot shapes, including the peripheral shape defined by the outer edge 72, allow for easy and rapid assembly, for example, by providing effective packing and suitable clearance between the turbine foot 54 and the obstacle 84. Figure 2It can also be seen that a plurality of bolt holes 84 are formed in the turbine foot 54 and extend between the engine side 56 and the turbine mounting side 58. The bolt holes 82 are arranged in a trapezoidal pattern consistent with the trapezoidal shape defined by the outer edge 72.

[0017] Now refer to Figure 3 The diagram shows a threaded stud bolt 112 positioned in and extending from bolt hole 82. The stud bolt 112 can be received in a registration bolt hole in turbocharger 22, coupled with a nut, and a washer and / or seal sandwiched therebetween. See also... Figure 4 The turbine support 54 also includes a first inner peripheral edge 86 (hereinafter referred to as "first inner edge 86") that forms a first exhaust outlet 88 from the first inlet exhaust duct 42 opening in the platform 60 and is configured to feed exhaust gas from the first set of engine cylinders into the turbine 24. The turbine support 54 also includes a second inner peripheral edge 90 (hereinafter referred to as "second inner edge 90") that forms a second exhaust outlet 92 from the second inlet exhaust duct 46 opening in the platform 60 and is configured to feed exhaust gas from the second set of engine cylinders into the turbine 24. The platform 60 thus surrounds the first exhaust outlet 88 and the second exhaust outlet 92.

[0018] The turbine support 54 even includes a web 94 extending between the first exhaust outlet 88 and the second exhaust outlet 92, which separates the turbine support 54 and divides the exhaust streams from the respective sets of combustion cylinders, which are fed into the turbine inlet 26 of the turbocharger 22. The first inner edge 86 and the second inner edge 90 each have varying peripheral curvatures, which are largest in magnitude of finite curvature on the web 94. "Largest in magnitude of finite curvature" refers to the curvature that is largest relative to the other curvatures of the inner edges 86 and 90, not an infinite curvature defined by linear or substantially linear edge segments. In other words, no inner edge 86 and 90 has a finite curvature greater than the curvature on the web 94.

[0019] The first inner edge 86 and the second inner edge 90 together form the hourglass web profile in the turbine mounting plane 62. It can be understood that the turbine mounting plane 62 is... Figure 4 The page is flat, so the hourglass outline is obvious. Also as shown, the first exhaust outlet 88 and the second exhaust outlet 92 can be mirror images of each other. From Figure 4It can also be seen that the hourglass web profile defines a principal axis 128 and a secondary axis 130 orthogonal to the long periphery base 74 and the short periphery base 76. The short axis 130 can be understood as bisecting the isosceles trapezoid defined by the outer edge 72 discussed above, wherein the first exhaust outlet 88 and the second exhaust outlet 92 are mirror images of each other in the opposite halves of the bisected isosceles trapezoid. The terms secondary axis and principal axis are used herein in a manner similar to the use of such terms in relation to hyperbolas. The hourglass shape can be a hyperbolic shape formed by a parabola, but is generally an hourglass shape formed by arc segments.

[0020] Each of the first inner edge 86 and the second inner edge 90 may respectively include curved peripheral segments 96 and 98 on the web 94, and have the aforementioned maximum finite curvature at least in the turbine mounting plane 62. Therefore, each curved peripheral segment 96 and 98 may also form an arc segment. Each of the first inner edge 88 and the second inner edge 90 may also respectively include an oriented linear peripheral segment 100 and 102 opposite to and parallel to the corresponding curved peripheral segments 96 and 98 and adjacent to the first peripheral leg 78 and the second peripheral leg 80. Each of the first inner edge 86 and the second inner edge 90 may also respectively include another linear peripheral segment 104 and 106 adjacent to the long peripheral base 74, and yet another linear peripheral segment 108 and 110 adjacent to the short peripheral base 76.

[0021] Continue to refer to Figure 4 Bolt holes 82 may include two long-span bolt holes 82 adjacent to the long peripheral base 74 and two short-span bolt holes 82 adjacent to the short peripheral base 76. The long span dimension 114 is defined between the center lines 116 of the respective two long-span bolt holes 82. The short span dimension 118 is defined between the center lines 120 of the respective two short-span bolt holes 82. It is reminiscent that the curved peripheral segments 96 and 98 may each form an arc segment. It should also be reminiscent that exhaust outlets 88 and 92 may be mirror images of each other; therefore, any description or discussion of one of the exhaust outlets 88 and 92 herein should be understood as referencing it in a similar manner to the other. The curved peripheral segment 98 defines the radius 126 of the circle 122, wherein the curved peripheral segment 98 forms an arc segment. Figure 4 As shown, in the left-right direction, circle 122 has a center point 124 that is relatively closer to the center of linear peripheral segment 102 than curved peripheral segment 98. Radius 126 can have different dimensions. By assembling peripheral segments of certain relative sizes, and by balancing and optimizing other geometric properties of turbine support 54, including exhaust outlet size and flow area, web crack resistance, and ease of exhaust system assembly and installation, as discussed further herein.

[0022] Therefore, the ratio of the radius size defined by radius 126 to the long span size 114 can be less than 32% or 0.32:1, and the ratio of the main body radius size to the short span size 118 can be greater than 32% or 0.32:1. In an improvement, the ratio of the main body radius size to the long span size 114 can be about 28% or 0.28:1, and the ratio of the main body radius size to the short span size 118 can be about 36% or 0.36:1. The ratio of the short span size 118 to the long span size 114 can be from 75% or 0.75:1 to 80% or 0.80:1, and in an improvement it can be from about 77% or 0.77:1 to about 78% or 0.78:1. Similarly, in a practical implementation, the first exhaust outlet 88 and the second exhaust outlet 92 together define a flow area, and the platform 60 also defines a platform area, and the ratio of the flow area to the platform area can be from 44% or 0.44:1 to 54% or 0.54:1. In an improvement, the ratio of the flow area to the platform area can be from about 48% or 0.48:1 to about 50% or 0.50:1. As used herein, the term “about” can be understood in the context of conventional rounding to a consistent number of significant figures. Thus, “about 0.48” means from 0.475 to 0.484, and so on.

[0023] Industrial applicability

[0024] As discussed above, the overall shape formed by the turbine support 54, such as an isosceles trapezoid, facilitates the assembly and installation of the turbocharger 22 within the exhaust system 20. It also provides a relatively large platform area within which the exhaust outlet area can be relatively large without requiring the outer wall or web 94 of the turbine support 54 to be excessively thin or noticeably radial, which could promote thermal fatigue cracking or cause other problems. Therefore, the inner periphery shape and proportions of the inner edges 86 and 90 can be understood as providing an optimized shape and flow area in conjunction with the outer periphery shape of the turbine support 54 itself. In other words, the exhaust outlets 88 and 92 provide an optimized flow area suitable for a trapezoidal or similar shape, while still providing sufficient web thickness and size, as well as wall thickness, to be relatively crack-resistant in response to thermal cycling and other factors during engine life or service range. The hourglass partition wall, as disclosed herein, along with other geometric and proportional properties, thus provide robustness and optimized flow area for inlet assembly on the exhaust manifold side, while trapezoidal or other similarly shaped supports facilitate easy assembly and installation of the exhaust manifold and turbine, ultimately reducing overall production time.

[0025] This specification is for illustrative purposes only and should not be construed as limiting the scope of this disclosure in any way. Therefore, those skilled in the art will understand that various modifications can be made to the embodiments currently disclosed without departing from the full and fair scope and spirit of this disclosure. Other aspects, features, and advantages will become apparent from a review of the accompanying drawings and claims. As used herein, the article “a” or “an” is intended to include one or more items and may be used interchangeably with “one or more.” The term “an” or similar language is used where only one item is intended. Furthermore, as used herein, the terms “has,” “have,” “having,” etc., are intended to be open-ended terms. Additionally, unless expressly stated otherwise, the phrase “based on” is intended to mean “at least partially based on.”

Claims

1. A turbine connector for an engine exhaust manifold, comprising: A turbine support foot having a turbine mounting side facing the engine side and defining a turbine mounting plane; The turbine support leg also includes an outer edge, the outer edge having a first peripheral base, a second peripheral base, and a first peripheral leg and a second peripheral leg extending between the first peripheral base and the second peripheral base, respectively; The turbine support leg further includes: a first inner edge forming a first exhaust outlet with an opening on the turbine mounting side; a second inner edge forming a second exhaust outlet with an opening on the turbine mounting side; and a web extending between the first exhaust outlet and the second exhaust outlet. The first inner edge and the second inner edge each have varying peripheral curvature and together form an hourglass web profile in the turbine mounting plane. The hourglass web profile is defined by a first axis extending between the first peripheral leg and the second peripheral leg, and a second axis orthogonal to the first axis. The varying peripheral curvature is maximized at a finite curvature magnitude on the web. The first inner edge and the second inner edge each have a curved segment on the web and a linear segment opposite to the corresponding curved segment, and each corresponding linear segment is arranged diagonally relative to the first axis and the second axis.

2. The turbine connector of claim 1, wherein the first peripheral base includes a long peripheral base, the second peripheral base includes a short peripheral base, and each of the first peripheral leg and the second peripheral leg extends at an angle between the first peripheral base and the second peripheral base.

3. The turbine connector according to claim 1, wherein the first shaft includes a main shaft, and the second shaft includes a secondary shaft orthogonal to the first peripheral base and the second peripheral base.

4. The turbine connector of claim 1, wherein each corresponding linear segment is parallel to an adjacent orientation of the first peripheral leg or the second peripheral leg.

5. The turbine connector of claim 4, wherein each of the first inner edge and the second inner edge includes a linear segment adjacent to the first peripheral base and a linear segment adjacent to the second peripheral base.

6. The turbine connector of claim 4, wherein each of the curved segments comprises an arc segment.

7. A turbine connector, comprising: A turbine support foot having an engine-facing side and a turbine mounting side opposite to the engine-facing side and defining a turbine mounting plane; The turbine support leg also includes an outer edge, which includes a first peripheral base, a second peripheral base, a first peripheral leg and a second peripheral leg extending between the first peripheral base and the second peripheral base; The turbine support also has a plurality of bolt holes therein, including two long-span bolt holes adjacent to the first peripheral base and two short-span bolt holes adjacent to the second peripheral base; A long span dimension is defined between the center lines of the two long span bolt holes, and a short span dimension shorter than the long span dimension is defined between the center lines of the two short span bolt holes; The turbine support leg further includes: a first inner edge forming a first exhaust outlet with an opening facing the turbine side; a second inner edge forming a second exhaust outlet with an opening facing the turbine side; and a web extending between the first exhaust outlet and the second exhaust outlet. Each of the first inner edge and the second inner edge includes a curved segment on the web, the curved segment forming an arc defining a radius size; and Each of the long span dimension and the short span dimension is greater than the radius dimension.

8. The turbine connector of claim 7, wherein each of the two long-span bolt holes and the two short-span bolt holes is closer to the outer edge than the first inner edge or the second inner edge.

9. The turbine connector of claim 7, wherein each arc lies on a circle intersecting one of the plurality of bolt holes.

10. The turbine connector of claim 9, wherein each circle intersects with one of the short-span bolt holes.

11. The turbine connector of claim 7, wherein the curved sections together form an hourglass web profile.

12. The turbine connector of claim 7, wherein the two long-span bolt holes and the two short-span bolt holes are arranged in a trapezoidal pattern.

13. The turbine connector of claim 12, wherein the trapezoidal pattern comprises an isosceles trapezoidal pattern.

14. The turbine connector of claim 13, wherein each of the curved segments forms the largest radius of curvature among all the radii of curvature of the first inner edge and the corresponding one of the second inner edges.

15. A turbine connector, comprising: A turbine support foot, the turbine support foot comprising: an outer edge having a first peripheral base and a second peripheral base; a first inner edge forming a first exhaust outlet; a second inner edge forming a second exhaust outlet; and a web extending between the first exhaust outlet and the second exhaust outlet; and The first inner edge and the second inner edge each include a curved segment on the web, a first linear segment adjacent to the first peripheral base, a second linear segment adjacent to the second peripheral base, and a third linear segment opposite to the corresponding curved segment. Each corresponding first linear segment includes a linear segment of medium length, each corresponding second linear segment includes a linear segment of shortest length, and each corresponding third linear segment includes a linear segment of longest length.

16. The turbine connector of claim 15, wherein the first peripheral base includes a long peripheral base and the second peripheral base includes a short peripheral base.

17. The turbine connector of claim 15, wherein each of the curved segments extends between a corresponding intermediate-length linear segment and a minimum-length linear segment, and each of the longest-length linear segments is oriented at an angle relative to the corresponding intermediate-length linear segment and the minimum-length linear segment.

18. The turbine connector of claim 15, wherein the first exhaust outlet and the second exhaust outlet together define a flow area, and the ratio of the flow area to the area defined between the outer edge and each of the first exhaust outlet and the second exhaust outlet is from 0.44:1 to 0.54:1.

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