Patent ID: 12234766

DETAILED DESCRIPTION OF THE DISCLOSURE

With reference to the FIGS., wherein like numerals indicate like parts throughout the several views, a schematic representation of a system30(i.e., an entryway system30) is shown inFIG.1. The system30includes a turbocharger32having a turbine portion33for receiving exhaust gas from an internal combustion engine34and a compressor portion35for delivering compressed air to the internal combustion engine34. Although not required, the turbocharger32is typically used in passenger and commercial automotive applications. However, it is to be appreciated that the turbocharger32may be used in non-automotive applications such as heavy equipment applications, non-automotive diesel engine applications, non-automotive motor applications, and the like.

The turbine portion33includes a turbine housing36having an interior surface38defining the turbine housing interior40. The turbine housing interior40is adapted to receive a turbine wheel42having a plurality of turbine blades (not shown), typically a plurality of evenly spaced turbine blades. In addition, the turbocharger32typically includes a turbocharger shaft44, a compressor wheel46, a compressor housing48, and a bearing housing50. During operation of the turbocharger32, the turbine wheel42(and in particular the turbine blades of the turbine wheel42) receives exhaust gas from the internal combustion engine34which causes the turbine wheel42to rotate. When present, the turbocharger shaft44is coupled to and rotatable by the turbine wheel42. When present, the compressor wheel46is disposed in the compressor housing48, is coupled to the turbocharger shaft44, and is rotatable by the turbocharger shaft44for delivering compressed air to the internal combustion engine34. The bearing housing50extends about the turbocharger shaft44between the turbine wheel42and the compressor wheel46. The turbocharger32also typically includes bearings52disposed about the turbocharger shaft44and in the bearing housing50for rotatably supporting the turbocharger shaft44.

The interior surface38of the turbine housing36also defines a plurality of volutes separated by walls, and hence the turbine housing36is defined as a divided volute turbine housing. In one exemplary embodiment, the divided volute turbine housing36is a dual volute turbine housing36, and hence the interior surface38defines a first volute54and a second volute56that are respectfully separated by a wall60. The wall60includes first and second tongues61,63(seeFIGS.3-9), which represent different portions of the wall60spaced from each other that separates portions of the first and second volutes54,56.

For case of description herein after, the turbocharger32will be further explained as including a dual volute turbine housing36. However, embodiments of turbine housings having additional numbers of volutes (e.g., three volutes or four volutes) are within the scope described herein.

The first and second volutes54,56are each in fluid communication with the internal combustion engine34and the turbine housing interior40for delivering exhaust gas from the internal combustion engine34to the turbine housing interior40. As also shown inFIG.1, the interior surface38also defines a turbine housing outlet58. The turbine housing outlet58is in fluid communication with the turbine housing interior40for discharging exhaust gas from the turbine housing interior40. In addition, the inner surface38also defines a wastegate (not shown) fluidically coupling each or either of the first and second volutes54,56to the turbine housing outlet58. The turbine housing36may be comprised of any suitable metal. Typically, the turbine housing36is comprised of iron or a steel alloy.

In certain embodiments, as also shown inFIG.1, the system30also includes a controller146that is coupled to turbocharger32and/or to the internal combustion engine34that controls the various other components of the turbocharger32and/or internal combustion engine34. The controller146may include one or more processors, or microprocessors, for processing instructions stored in memory150to control various functions on the turbocharger32related to the introduction of the exhaust gas within the turbine housing interior40through the first and second volutes54,56. Such instructions may be any of the functions, algorithms or techniques described herein performed by the controller146. Additionally, or alternatively, the controller146may include one or more microcontrollers, field programmable gate arrays, systems on a chip, discrete circuitry, and/or other suitable hardware, software, or firmware that is capable of carrying out the functions described herein. In some embodiments, the controller146is an engine control unit (ECU) that controls the various other components of the turbocharger32and/or internal combustion engine34. In embodiments where the controller146is the engine control unit, the controller146is separate from the turbocharger32. In other words, the controller146is a separate component that is not included on or in the turbocharger32. In other embodiments, the controller146is discrete from the ECU. For example, the controller146may be included on or in the turbocharger32. In other words, the controller146is a component included on or in the turbocharger32. With reference toFIG.1, the system30may include the turbocharger32, the internal combustion engine34, and the controller146. Typically, the system30also includes at least one sensor148.

While not illustrated inFIG.1, the internal combustion engine34includes a plurality of cylinders. For example, the internal combustion engine34may include two cylinders, four cylinders, six cylinders, eight cylinders, or more cylinders. The internal combustion engine34may also include an odd number of cylinders (e.g., three cylinders or five cylinders). The internal combustion engine34may have a V-engine configuration, a flat/boxer engine configuration, a W-engine configuration, an inline engine configuration, and the like. In the illustrated embodiment, the internal combustion engine34has an inline engine configuration. The internal combustion engine34includes a first group of cylinders and a second group of cylinders, with the first and second groups of cylinders each typically including half of the cylinders that are included in the internal combustion engine34. The first and second groups of cylinders produce exhaust gas in a series of pulses corresponding to an exhaust stroke of each of the first and second groups of cylinders. Timing of the exhaust strokes of the cylinders is such that pulses of exhaust gas are alternately emitted from the first group of cylinders and the second group of cylinders. The area of the first volute54, in combination with the produced gas from the exhaust stroke of the first set of cylinders, defines a first volute flow parameter. Similarly, the corresponding area of the second volute56, in combination with the produced gas from the exhaust stroke of the second set of cylinders, defines a second volute flow parameter. The volute flow parameter8for a volute (such as the first and second volute flow parameter of the respective first and second volute54,56(as provided herein)) is calculated by the equation:

δ=m˙⁢TP
wherein m is the mass flow through the volute, T is the exhaust gas temperature at the inlet of the volute, and P is the exhaust gas pressure at the inlet of the volute. Typically, the volute flow parameter8is measure for each respective exhaust stroke of the respective one of the first and second set of cylinders.

As noted above typically the first group of cylinders are in fluid communication with the first volute54and the second group of cylinders are in communication with the second volute56. In this manner, pulses of exhaust gas from the first and second groups of cylinders flow through the first and second volutes54,56, respectively, and to the turbine housing interior40, where the pulses of exhaust gas rotate the turbine wheel42. The respective pulses of exhaust gas flowing through the first volute54from the first group of cylinders (typically measured for each exhaust stroke) and area of the first volute54define a first volute flow parameter, while the respective pulses of exhaust gas flowing through the second volute56from the second group of cylinders (again typically measured for each exhaust stroke) and area of the second volute56define a second volute flow parameter. Owing to the difference in sizes of the areas of the first and second volutes54,56, the first and second volute flow parameters are generally different from one another.

In addition to the turbocharger32, as also shown inFIG.2, the entryway system30also includes a vane ring100(also referred to as a VTG cartridge or Vane Pack Assembly) disposed in the turbine housing interior40between the first and second volutes54,56and around the turbine wheel42, with the vane ring having plurality of vanes, shown as first and second set of vanes130and140, rotatably disposed to the vane ring100in an asymmetric vane pattern. The entryway system30also includes a plurality of spacers400disposed in a spaced apart manner on the vane ring100, with the vanes on the vane ring100and spacers400functioning to control the flow of exhaust gas flowing from the one or more volutes54,56to the turbine wheel42. In particular, the spacers400function to minimize flow disturbance of exhaust gas flowing from the one or more volutes54,56to the turbine wheel42.

The vane ring100includes an annular disk101disposed in the turbine housing interior40between the divided first and second volutes54,56and the turbine wheel42. In certain embodiments, the vane ring100includes two spaced apart annular disks101A,101B (the annular disk101A may sometimes referred to as a first annular disk101A or lower vane ring (LVR)101A, while disk101B may sometimes referred to as a second annular disk101B or upper vane ring (UVR)101B), which the plurality of vanes130,140rotatably disposed between the vane rings100A,100B in the afore-mentioned vane pattern. The vane ring100includes the plurality of vanes130,140(shown as first and set of vanes130and140inFIGS.2-9) rotatably disposed to the vane ring100in a prespecified vane pattern. In these embodiments, the spacers400also function to provide an axial separation function between the first and second annular disks101A,101B, and thereby maintain clearance between the annular disks101A,101B and the vanes130,140.

Each of the annular disks101A and101B includes a vane ring surface102which includes an inner vane ring surface102A and an opposing outer vane ring surface102B extending between an inner circumferential edge104and an outer circumferential edge106. The inner circumferential edge104defines a circular orifice for receiving the turbine wheel42of the turbocharger32. In particular, the vane ring100is disposed in the turbine housing36with the first and second tongue61,63each separately terminating at a position adjacent to the outer circumferential ring106.

Each of the annular disks101A and101B also defines a plurality of first openings107within the inner vane ring surface102A between the inner circumferential edge104and an outer circumferential edge106, with the number of openings107corresponding to the number of the plurality of vanes130,140and configured to receive a shaft139,149of a respective one of the plurality of vanes130,140, as will be explained further below. The openings107therefore further define the vane pivot point (VPP) of the respective one vane of the plurality of vanes130,140disposed therein. InFIG.2that includes the first and second annular disks101A,101B, the plurality of openings107in at least one the first and second annular disks101A,101B extend from the inner vane ring surface102A to the outer vane ring surface102B such that the entirety of the second shafts137,147extends through the opening107of the second annular disk101B and such that the vane levers153are positioned within the turbine housing interior40between the outer vane ring surface102B of the second annular disk101B and the turbine housing36.

As also shown inFIG.2, a vane lever153is coupled, and preferably fixed via riveting or welding, to the second shafts137,147of the vanes130,140and also includes a flange portion159. The vane levers153are configured to rotate each of the vanes130and140in a coordinated manner about their respective vane pivot point (VPP) between a closed position and an open position and through one or more intermediate positions, as will be explained further below. An adjustment ring199is retained between the vane levers153and the second annular disk101B, with the flange portion159of each of the vane levers153disposed within an opening in the adjustment ring199. An assembly203including a pin205and block207is affixed to the adjustment ring199, such as by riveting or welding, with a pivot having a pivot shaft (not shown) connecting the assembly203. The pivot shaft is rotated by a linkage (not shown) connected to an actuator (not shown). The actuator rotates the linkage on the basis of a particular engine operating condition to adjust the flow of exhaust gas through the vanes130,140. In particular, the actuator rotates the linkage, which rotates the pivot shaft and adjustment ring199through the assembly203. The rotation of the adjustment ring199causes the adjustment ring199to contact the flange portion159of the vane levers153and rotates the vane levers153in response, which in turn causes the coupled vanes130,140to move between the closed and open positions and through one or more intermediate positions to adjust the flow of exhaust gas through the vanes130,140on the basis of an engine operating condition, such as engine speed. The closed position, as defined below, is a position in which the pulses of gas from the respective volutes54,56through the respective vanes130,140is minimized, while conversely the open position is a position in which the pulses of gas from the respective volutes54,56through the respective vanes130,140is maximized. Intermediate positions are therefore positions in which the pulses of gas from the respective volutes54,56through the respective vanes130,140are between a minimum and maximum value.

Referring now toFIG.3, which generally represents one configuration of vanes130,140for the entryway system30in a baseline configuration, the first set of vanes130(i.e., a first set of at least two vanes130) are rotatably disposed in a spaced apart manner from one another on the vane ring surface102such that the first set of vanes130are positioned downstream of the first volute54. Still further, the second set of vanes140are rotatably disposed in a spaced apart manner from one another such that the second set of vanes140(i.e., a second set of at least two vanes140) are positioned downstream of the second volute56. Each of the vanes130,140are rotatable along the vane ring surface102, and in particular are rotatable along the inner vane ring surface102A of a respective annular ring101A,101B about a vane pivot axis between a closed position and an open position and through one or more intermediate positions between the closed and open position. The vane pivot axis, as defined herein, extends in a direction normal to a plane defining the vane ring surface102of the vane ring100.

Still further, in the embodiment illustrated inFIG.3, the first set of vanes130includes six vanes130positioned adjacent to one another of the vane ring surface102around the vane ring100, while the second set of vanes140includes five vanes140positioned adjacent to one another of the vane ring surface102around the vane ring100. Accordingly, there are a total of eleven vanes130,140on the vane ring102in the embodiment ofFIG.3, which provide exhaust flow to the turbine wheel42having a total of eleven equally spaced turbine blades45. While the embodiments provided herein include eleven vanes130,140and eleven turbine blades45, alternative relative amounts of vanes and blades are contemplated, preferably wherein the number of vanes130,140is an odd number, such as a prime number (such as, for example, inFIG.2which illustrates thirteen vanes130,140). In addition, each of the vanes130and140includes a vane blade131or141each having a respective inner surface131A,141A and an opposing outer surface131B,141B with each of the vanes130,140extending in length between a leading edge132,142and a trailing edge134,144and extending in width between the inner surface131A,141A and the opposing outer surface131B,141B.

FIG.3illustrates a baseline configuration of the annular disk101of the vane ring100with rotatable vanes130,140rotatably disposed thereon for use in the entryway system30ofFIG.1in which the first and second volutes54,56are configured with first and second volute54,56separation, with each volute54,56having an identical respective (minimum) cross-sectional area defined as the volute throat, just upstream of the interface with the vane ring100, alternatively referred to as identical critical throat areas at the interface with the vane ring100. The positioning of the first and second tongues61,63are configured wherein a first tongue clocking angle between the first and second tongues61,63corresponding to the first arcuate region105is less than 180 degrees (seeFIG.3), while a second tongue clocking angle between the between the first and second tongues61,63corresponding to the second arcuate region115(also seeFIG.3) is greater than 180 degrees, with the total combined degrees of the first and second clocking angles equals 360 degrees. In further embodiments, the positioning of the first and second tongues61,63are configured wherein a first tongue clocking angle between the first and second tongues61,63corresponding to the first arcuate region105is greater than 180 degrees (seeFIG.3), while a second tongue clocking angle between the between the first and second tongues61,63corresponding to the second arcuate region115(also seeFIG.3) is less than 180 degrees, with the total combined degrees of the first and second clocking angles equals 360 degrees. In still further embodiments, the first and second clocking angles may each be 180 degrees, but wherein there is a degree of asymmetry in the vane configuration of the vanes130,140, such as through asymmetric vane spacing.

InFIG.3, the entryway system30having a baseline configuration is configured wherein each of the respective vanes130,140is the same, with each of the respective vane pivot points (VPP) of the respective vanes130,140(corresponding an axis defined by the length of the first shaft133,143and an opposing second shaft137,147of the respective vanes130,140and corresponding to the openings107in the annular disk101A) being located along the same circumferential vane pitch circle radii from a center rotation axis with each of the first shaft133,143and an opposing second shaft137,147of the respective vanes130,140located in certain embodiments approximately midway between the inner circumferential edge104and the outer circumferential edge106, although in other embodiments the position may be closer to or further from the inner circumferential edge104. Still further, the vane spacing (β) of each of the respective eleven vanes130,140, as shown inFIG.3, corresponds to an equiangular vane spacing angle (β) of about 32.7 degrees.

In certain embodiments, the second shaft137is an extension of the first shaft133, and the second shaft147is an extension of the first shaft141. In still further embodiments, the second shaft137is an extension of and integrally formed with the first shaft133, and the second shaft147is an extension of and integrally formed with the first shaft141. In these embodiments, the first and second shaft133,137of vane130may simply referred to as a shaft139of vane130, while the first and second shaft143,147of vane140may simply referred to as shaft149of vane140.

Still further, in the baseline configuration ofFIG.3, the virtual extension of an extended length of one vane130A (i.e., an aligned one vane130A, also referred to as a tongue vane130A or first tongue vane130A) of the first set of vanes130, defining by a vane axis230A or first vane axis230A, is aligned along a first tongue axis213defined by a virtual extended length of the first tongue61, while the virtual extension of an extended length of one vane140A (i.e., an aligned one vane140A, also referred to as a tongue vane140A or second tongue vane140A) of the second set of vanes140, defining a vane axis240A or second vane axis240A, is aligned along a second tongue axis211defined by a virtual extended length of the second tongue63when the tongue vanes130A,140A are in an open position. The length of a respective vane130,140(including the length of the respective tongue vane130A,140A), is the distance between a leading edge132,142and a trailing edge134,144of each respective vane130,140. When the respective axis213,230A along the tongue vane130A and first tongue61are collinear or generally parallel to one another and close to collinear, the axis230A of the tongue vane130A is defined herein to be aligned along the axis213with the first tongue61. Similarly, when the respective axis240A along the tongue vane140A and the axis211along the second tongue63are collinear or generally parallel to one another and close to collinear, the axis240A of the tongue vane140A is defined herein to be aligned along the axis211with the second tongue63.

Still further, in the baseline configuration ofFIG.3, the length of the tongues61,63extends all the way to the outer diameter106of the vane ring100, and as illustrated to the outer diameter of each of the respective annular disks101A,101B. Accordingly, in the baseline configuration ofFIG.3, when the vanes130,140are positioned in the closed position, the pulses of exhaust gas from the cylinders via the respective volute54,56through the respective vanes130,140to the turbine wheel42can be precisely controlled in order to optimize turbine stage efficiency, pulse capture and engine BSFC reduction while maintaining benefits for thermal management, engine braking, and efficiency towards rated and transient response. Notably, there is minimal leakage of exhaust gas between the aligned one vane130A and the first tongue61, and between the aligned one vane140A and the second tongue63.

However, while providing these benefits, the baseline configuration ofFIG.3exhibited wear in various VTG components, and in particular to the vane levers153associated with the vanes130,140adjacent to the tongues61,63of the wall60, the adjustment ring199, and the annular disk101A,101B of the vane ring100. This increased wear is believed to be attributed in part, and in certain embodiments in a significant part, due to increased aerodynamic forces of the pulses of exhaust gas and mechanical loads in the VTG mechanism for the entryway system30, especially from pressure reversals through flow in each volute54,56, which leads to the afore-mentioned wear in the various VTG components described immediately above.

In the exemplary embodiments of the subject application disclosed herein inFIGS.4-9, various methods of manipulating the aerodynamic forces and/or subsequent mechanical loads in the VTG mechanism of the entryway system30are provided that include individual or various combinations of vane geometry, vane fixation, vane spacing, spacer geometry, vane to tongue relationship, and/or vane to housing relationship. By manipulating the aerodynamic forces and/or subsequent mechanical loads in the VTG mechanism, VTG component wear can be mitigated during normal usage of vehicles or components of engines.

In each of these alternative embodiments ofFIGS.4-9, modifications of one or more components of the VTG mechanism, or the location of these components, of the baseline configuration ofFIG.3are provided that do not significantly impact the performance characteristics of the modified entryway system30in terms of optimized turbine stage efficiency, pulse capture and engine BSFC reduction as compared to the baseline configuration ofFIG.3, all while maintaining benefits for thermal management, engine braking, and efficiency towards rated and transient response similar to that ofFIG.3. Notably, however, each of the alternative embodiments reduces the aerodynamic forces and/or subsequent mechanical loads in the VTG mechanism of the entryway system30and thereby reduce or mitigate the wear on the VTG components that may occur in the baseline configuration ofFIG.3.

In one exemplary embodiment, as illustrated inFIG.4, the location of the vanes130are configured such that the respective closest one vane130B, also referred to as the first tongue vane130B, of the first set of vanes130is adjacent to the first tongue61, but wherein the first tongue vane axis230B (defined by the extended virtual length of the first tongue vane130B) is not aligned along the first tongue axis211when the first tongue vane130B is in the open position. In addition, the location of the vanes140are configured such that the respective closest one vane140B, as referred to as the second tongue vane140B, of the second set of vanes140is adjacent to the second tongue63, but wherein the virtual extended length of the second tongue vane140B, which defines a second tongue vane axis240B, is not aligned along a second tongue axis213when the second tongue vane140B in the open position. InFIG.4, and corresponding to the definition of adjacent to as provided herein, the respective tongue vanes130B,140B represent the closest adjacent vane130,140of each of the first and second set of vanes130,140to the respective tongue61,63, This alternation of the location of the respective tongue vanes130B,140B from the baseline configuration inFIG.3(which include the adjacent tongue vanes130A,140A which define respective tongue axes230A,240A and which are aligned with the respective tongue axes211,213when the adjacent tongue vanes130A,140A are in the open position) allows a small portion of leakage of exhaust gas between the first tongue vane130B and the first tongue61, and between the second tongue vane140B and the second tongue63in any relative vanc position (i.e., open, closed, or in an intermediate position), and in particular in the open vane position. This small leakage of exhaust gas between the adjacent vane130B,140B and the respective tongue vane61,63lessens the aerodynamic forces and mechanical loads applied onto the respective vanes130,130B140,140B in the closed position or in any van position, which in turn lessens the mechanical loads and wear of the components that are impacted by the forces applied to the vanes130B,140B as compared with the baseline configuration inFIG.3with aligned vanes130A,140A. For example, less wear was exhibited over the same testing cycle on the vane levers153that were coupled to the respective vanes130B,140B, as well as wear on the adjustment ring199adjacent to the location of these vane levers153, as compared to vanes130A,140A, in the baseline configuration ofFIG.3. In the particular embodiment ofFIG.4, the entirety of the vane ring100and vanes130,140are clocked (i.e., pivoted) relative to the baseline configuration ofFIG.3, and hence each of the respective vanes130,140,130B,140B, are clocked/pivoted while maintaining the respective spacing of the vanes130,140on the vane ring100.

In another exemplary embodiment, as illustrated inFIG.5, in addition to adjusting the location of the vanes130,130B,140,140B as inFIG.4by clocking as described above to create the leakage gaps between the adjacent vanes130B,140B and the respective tongue vanes61,63, an asymmetric spacing between adjacent vanes130,130B,140,140B is also provided. For example, as shown inFIG.5, the adjacent spacing between two adjacent vanes140and140B was β′, while the spacing between adjacent vanes140B and130was increased to β″. Accordingly, during a closed condition, leakage of exhaust gas between the vane140B and the adjacent vane130of the first set of vanes130, or between adjacent vanes140and140B of the second set of vanes140can also occur, small leakage of exhaust gas, which lessens the aerodynamic forces and mechanical loads applied onto the respective vanes130,130B,140,140B in the closed position and provides similar wear reduction in the VTG components as inFIG.4.

In another exemplary embodiment, as illustrated inFIG.6, as opposed to manipulating the vanes130,130B,140,140B as inFIGS.4and5, the length one or both of the respective tongues61,63is shortened such that it does not extend to the outer circumference106of the vane ring100(or either of the annular rings101A,101B). Accordingly, in the closed position, a gap425,435still exists between the respective vanes130A,140A and the respective tongues61,63. This alternation of the location of the tongues61,63away from the respective aligned vanes130A,140A allows a small portion of leakage of exhaust gas between the adjacent tongue vane130A and the first tongue61, and between the adjacent tongue vane140A and the second tongue63, in any vane position through the respective gaps425,435. This small leakage of exhaust gas through the respective gaps425,435is believed to lessen the aerodynamic forces and mechanical loads applied onto the respective vanes130,130A,140,140A in any vane position in the same manner described above inFIG.4as compared with the baseline configuration inFIG.3, which in turn is believed to lessen the mechanical loads and wear of the components that are impacted by the forces applied to the vanes130,130A,140,140A inFIG.4as compared with the baseline configuration inFIG.3.

In still other exemplary embodiments, as illustrated inFIGS.7A,7B, and7Cfor use in altering the baseline configuration of the entryway system30ofFIG.3or for use in the configurations of the entryway system ofFIGS.4and5, various modifications are made to one or more of the vanes130,140themselves that allow for exhaust gas leakage either between the vanes130,140or through the vanes130,140when the vanes are rotated to a closed position.

Referring first toFIG.7A, another exemplary embodiment is illustrated in which one or both of the leading edge132,142and the trailing edge134,144of the vane blade131,141of one or more of the vanes130,140(i.e., the distance between the leading edge132,142and a pivot point PP (i.e., a pivot axis PP), or the trailing edge trailing edge134,144and the pivot point PP, or both) is altered as compared to the baseline configuration as illustrated inFIG.3. More in particular, the distance between the leading edge132,142and its pivot point PP of its respective shaft139,149of the vane blade131,141of one or more of the respective vanes130,140, and/or the distance between the trailing edge134,144and its pivot point PP respective shaft139,149of the vane blade131,141of one or more of the respective vanes130,140, is shortened as compared to the baseline configuration ofFIG.3. As illustrated inFIG.7A, the original leading edge132,142and the trailing edge134,144of the vane blade131,141as inFIG.3are respectively shown in phantom lines, while the newer leading edge132′,142′ and the trailing edge134′,144′ of the respective vane blade131,141in accordance with the exemplary embodiment ofFIG.7Aare illustrated in solid lines.

This shortening of the vane blade131,141of one or more of the respective vanes130,140allows a small portion of leakage of exhaust gas between any pair of adjacent vane blades (i.e., between adjacent vane blades131of the first set of vanes130; adjacent vane blades141of the second set of vanes140, and/or between adjacent vane blades131and141of a respective pair of vanes130and140) when the vanes130,140are rotated about the new pivot point PP′ to the closed position (i.e., a leakage gap (a representative leakage gap215is shown in phantom in FIG.3with the vane130altered as inFIG.7—although this gap215is not actually present in the configuration ofFIG.3which illustrates equal length vanes130,140that close in a manner wherein leakage gaps are not present but is merely representative of where such a gap would be in the configuration ofFIG.7) is created between the newer leading edge132′,142′ and the adjacent trailing edge134,144or134′,144′ of a respective pair of adjacent vane blades131,131of a pair of vanes130,130; a respective pair of adjacent vane blades141,141of a respective pair of vanes140,140; or a respective pair of vane blades131,141of a respective pair of vanes130,140; when rotated to the closed position). Similar to the embodiments ofFIGS.4-6, this leakage gap215lessens the mechanical loads and wear of the VTG components that are impacted by the aerodynamic forces applied to the vanes130,140.

Referring next toFIG.7B, yet another exemplary embodiment is illustrated in which the relative location of the shafts139,149on one or both of the vane blades131,141of the baseline configuration as illustrated inFIG.3are shifted to a new position (identified as133′,137′,143′,147′ in phantom inFIG.7B) relative to their respective leading edge132,142and trailing edge134,144of the respective vane blade131,141but wherein the overall length of the vane blades131,141of the baseline configuration as illustrated inFIG.3between the respective leading edge132,142and trailing edge134,144remains constant. This shifting changes the pivot point PP of the respective vane130,140of the baseline configuration ofFIG.3to pivot point PP′ (also shown by arrow PP′ in phantom inFIG.7B), which changes the pressure profile applied to the vanes130,140which can change the aerodynamic forces and mechanical loads applied onto the respective vanes130A,140A in any vane position to mitigate the mechanical loads and wear of the components that are impacted by the forces applied to the vanes130,140in a manner similar to allowing leakage as inFIGS.4-6and7A.

In certain embodiments, the shifting is such that a first distance, defined as the distance between the respective leading edge132,142of one vane130,140and the pivot point PP, is less than a second distance defined between the respective leading edge132′,142′ and the new pivot point PP′ of the same, but modified, one vane130,140(and wherein a first distance between the respective trailing edge134,144of one vane130,140and the pivot point PP, is greater than a second distance defined between the respective trailing edge134′,144′ and the new pivot point PP′ of the same, but modified, one vane130,140).

In still another alternative (not shown), the shifting could be in the opposite direction, in which the shifting is such that a first distance, defined as the distance between the respective leading edge132,142of one vane130,140and the pivot point PP, is greater than a second distance defined between the respective leading edge132′,142′ and the new pivot point PP′ of the same, but modified, one vane130,140(and wherein a first distance between the respective trailing edge134,144of one vane130,140and the pivot point PP, is less than a second distance defined between the respective trailing edge134′,144′ and the new pivot point PP′ of the same, but modified, one vane130,140).

In still further related embodiments, vane blades130,140are also contemplated having a combination of attributes ofFIGS.7A and/or7B. In particular, in one exemplary embodiment one but less than all of the vane blade130or140may be shortened as inFIG.7A, while another one but less than all of the vane blade130or140may be shifted as inFIG.7B. In still further exemplary embodiments, one or more but less than all of the vanes130or140may be shortened and shifted.

Referring next toFIG.7C, still yet another exemplary embodiment is illustrated in which a slot opening230is defined through one or more of the vanes130,140between the inner surface131A,141A and the outer surface131B,141B (with the distance140between the inner surface131A,141A and the outer surface131B,141B as defined as the width of the respective vane130,140) in a location between the respective leading edge132,142and trailing edge134,144. This slot opening230functions as a leakage path for exhaust gas through the vanes130,140when the vanes130,140in any vane position, including a closed position. Similar to the embodiments ofFIGS.4-6, this leakage through the slot230lessens the mechanical loads and wear of the VTG components that are impacted by the aerodynamic forces applied to the vanes130,140.

In still a further related embodiment toFIGS.7A-7C, a vane configuration can be presented in which one or more of the first and second set of vanes130,140includes a combination of the features ofFIG.7AandFIG.7B, alone or in combination with the features ofFIG.7C. By way of example, one vane130and140of either or each of the first and second set of vanes130,140could be shortened as described and illustrated above inFIG.7A, whereas another vane130and/or140or wherein the same vane130and/or140of each of the first and second set of vanes could have a shifted pivot point PP as described and illustrated above inFIG.7B, and where any one of the vanes130,140in this alternative configuration includes the slot opening230as described and illustrated above inFIG.7C.

In yet another exemplary embodiment, as illustrated inFIG.8, typically used in conjunction with the alternative vane130,140arrangement ofFIG.5in which the adjacent vane130B,140B is not aligned along an axis with the respective tongue61,63(as also shown inFIG.4) and in which asymmetric vane spacing is utilized, a first one400A of the plurality of spacers400is positioned adjacent to the first tongue61of the wall60, while a second one400B of the plurality of spacers is positioned adjacent to the second tongue63of the wall60. The term “adjacent to”, as defined herein with respect to the relationship of the first one400A and second one400B of the spacers400, refers to the positioning of the respective first one400A or second one400B of the spacers circumferentially outward of the vanes130A,140A and along a radial line (RL) extending from the axis of rotation of the turbine wheel42to the respective first or second tongue61,63. The respective first one400A or second one400B may be positioned adjacent to the outer circumferential ring106such that the respective first one400A or second one400B of the spacers400is aligned and generally flush to the respective first or second tongue61,63, or may be positioned slightly inward of the outer circumferential ring106so that a small gap may exist between the respective first one400A or second one400B of the spacers400and the respective first or second tongue61,63. In addition, the respective circumferentially inward most portion of the respective first one400A or second one400B are generally spaced circumferentially outward a sufficient distance from a respective adjacent one of the vanes130A,140B to allow the vane130A,140B to rotate between the open and closed position.

In addition to assisting in adjusting the flow of exhaust gas entering from the respective first or second volute54,56prior to being received by the turbine blades of the turbine wheel42, the first one400A and second one400B of the spacers400function to reduce scroll to scroll leakage that occurs between one of the vanes130A,140A and one of the respective tongues61,63during operation of the entryway system30in each of the intermediate positions and open position as compared with entryway systems that do not include such spacers400A,400B. However, because the first one400A and the second one400B of the spacers400do not contact the respective vanes130A or140A in the closed position, a small portion of leakage of exhaust gas between the vane130A and the first one400A spacer, and between the vane140A and the second one spacer400B in any vane position. This leakage of exhaust gas lessens the aerodynamic forces and mechanical loads applied onto the respective vanes130A,140A in the closed position in the same manner described above inFIG.4, which in turn lessens the mechanical loads and wear of the components that are impacted by the forces applied to the vanes130A,140A.

In yet a still further embodiment, as illustrated inFIG.9, the adjacent vanes130A and/or140A may be fixed vanes, referred to by reference numbers130A′,140A′, as opposed to rotating vanes130A,140A as in the baseline configuration ofFIG.3. In this embodiment, the remainder of the first set of vanes130and second set of vanes140remain as rotatable vanes130,140. These fixed vanes130A′,140A′ are welded or otherwise secured to the annular ring101A, and thus do not rotate in conjunction with the rotation of the remainder of the first set of vanes130and second set of vanes140between the open and closed position. As such, when the first set of vanes130and second set of vanes140are rotated to the closed position, a gap still exists between the respective fixed vanes130A′,140A′ and the respective tongues61,63. This allows a small portion of leakage of exhaust gas between the fixed vane130A and the first tongue61, and between the vane140A and the second tongue63in any vane position. Still further, a small portion of leakage of exhaust gas also occurs between the fixed vane130A′ or140A′ and adjacent respective ones of the first and second set of vanes130,140. These paths of leakage all individually lessens the mechanical loads and wear of the components that are impacted by the forces applied to the fixed vanes130A′,140A′ and other vanes130,140during usage.

In still further embodiments, any combination of the features of the embodiments ofFIGS.4-9may be used in combination with each other, which combines the features to create varying alternative paths of leakage that all individually or in combination lessen the mechanical loads and wear of the components that are impacted by the forces applied to the vanes130,140(movable or fixed) during usage as compared to those provided in the baseline configuration ofFIG.3.

The disclosure has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present disclosure are possible in light of the above teachings, and the disclosure may be practiced otherwise than as specifically described.