VARIABLE TURBINE GEOMETRY ASSEMBLY WITH TURBOCHARGER

Abstract

A variable turbine geometry assembly (10) for controlling the flow of exhaust gas to a turbine wheel (12) of a turbocharger (14), the variable turbine geometry assembly (10) comprising: an adjusting ring (16) extending along an axis (A1) and rotatable about it, at least one blade lever (18) coupled to the adjusting ring (16), at least one blade (20) coupled to the at least one blade lever (18), wherein the at least one blade (20) is movable relative to the adjusting ring (16) when the adjusting ring (16) rotates about the axis (A1), and a prestressing element (22), which is coupled to the adjusting ring (16) at a first circumferential location (24) on the adjusting ring (16), which is coupled to the adjusting ring (16) at a second circumferential location (26) which is different from the first circumferential location on the adjusting ring (16), which extends from the first circumferential point (24) on the adjusting ring (16) to the second circumferential point (26) on the adjusting ring (16) and which is operatively in contact with the at least one blade lever (18) between the first circumferential location (24) and the second circumferential location (26) to bias the at least one blade lever (18) towards the adjusting ring (16) and To reduce vibration between the adjusting ring (16) and the at least one blade lever (18).

Description

1. Field of the invention

[0001] The invention generally relates to a variable turbine geometry assembly for controlling the flow of exhaust gas to a turbine wheel of a turbocharger. 2. Description of the state of the art

[0002] Turbochargers take exhaust gas from an internal combustion engine and deliver pressurized air to the internal combustion engine. Turbochargers are used to increase the power output of the internal combustion engine, reduce the fuel consumption of the internal combustion engine, and reduce emissions produced by the internal combustion engine. The delivery of pressurized air to the internal combustion engine by the turbocharger allows the internal combustion engine to be smaller, yet capable of developing the same or a similar amount of horsepower as larger naturally aspirated internal combustion engines. Having a smaller internal combustion engine for use with a vehicle reduces the mass and aerodynamic frontal area of ​​the vehicle, which helps to reduce the fuel consumption of the internal combustion engine and improve the vehicle's fuel economy.

[0003] Typical turbochargers include a turbine housing defining a turbine housing interior, a turbine wheel disposed within the turbine housing interior for receiving exhaust gas from the internal combustion engine, and a shaft coupled to and rotatable thereby. Typical turbochargers also include a compressor housing defining a compressor housing interior, and a compressor wheel disposed within the compressor housing interior and coupled to the shaft, with the compressor wheel rotatable by the shaft for delivering compressed air to the internal combustion engine. Specifically, energy from the exhaust gas from the internal combustion engine, which would normally be wasted, is used to rotatably drive the turbine wheel, which is used to rotatably drive the shaft and, in turn, rotatably drive the compressor wheel to compress air and deliver compressed air to the internal combustion engine.

[0004] Turbochargers generally include a variable turbine geometry assembly arranged around the turbine wheel. Variable turbine geometry assemblies are known to control the flow of exhaust gas to the turbine wheel of the turbocharger. Document EP 3 988 767 A1 relates to a radial gas turbine with a gas supply device comprising a first and second limiting plate, as well as guide vanes arranged therebetween with levers and a connecting ring that is rotatable and provided for actuating the levers. DE 10 2017 218 050 A1 describes a turbocharger device having an annular spring element for axially bracing a guide vane of a variable turbine geometry against a turbine housing.However, prior art variable turbine geometry assemblies can fail due to repeated wear on various components of the variable turbine geometry assembly caused by vibrations between the various components of the variable turbine geometry assembly. Wear on components of the variable turbine geometry assembly caused by vibrations between various components of the variable turbine geometry assembly can lead to increased noise, further increased vibration, and increased noise, vibration, and harshness (NVH) of the turbocharger. Furthermore, component wear can also lead to functional failure of the variable turbine geometry assembly, resulting in the variable turbine geometry assembly being unable to adequately control the flow of exhaust gas to the turbocharger turbine wheel.

[0005] Therefore, there is still a need for an improved variable turbine geometry assembly for a turbocharger. SUMMARY OF THE INVENTION AND ADVANTAGES

[0006] The present disclosure relates to a variable turbine geometry assembly for controlling the flow of exhaust gas to a turbine wheel of a turbocharger according to claim 1, and to a turbocharger comprising the assembly according to claim 10. The dependent claims describe advantageous embodiments of the assembly. A variable turbine geometry assembly for controlling the flow of exhaust gas to a turbine wheel of a turbocharger includes an adjustment ring extending along and rotatable about an axis. The variable turbine geometry assembly also includes at least one vane lever coupled to the adjustment ring and at least one vane coupled to the at least one vane lever. The at least one vane is movable relative to the adjustment ring when the adjustment ring rotates about the axis.The variable turbine geometry assembly further includes a biasing member coupled to the adjustment ring at a first circumferential location on the adjustment ring and coupled to the adjustment ring at a second circumferential location different from the first circumferential location on the adjustment ring. The biasing member extends from the first circumferential location on the adjustment ring to the second circumferential location on the adjustment ring. The biasing member operatively contacts the at least one vane lever between the first circumferential location and the second circumferential location to bias the at least one vane lever toward the adjustment ring and reduce vibration between the adjustment ring and the at least one vane lever.

[0007] Accordingly, operatively contacting the biasing member with the at least one vane lever to bias the at least one vane lever toward the adjustment ring and reduce vibration between the adjustment ring and the at least one vane lever reduces wear between various components of the variable turbine geometry assembly. More specifically, reduced vibration between the adjustment ring and the at least one vane lever reduces wear on the adjustment ring and the at least one vane lever. Reduced wear on the adjustment ring and the at least one vane lever further reduces noise, vibration, and harshness (NVH) of the turbocharger and lowers the likelihood of a functional failure of the variable turbine geometry assembly that adequately controls the flow of exhaust gas to the turbine wheel of the turbocharger.Furthermore, coupling the biasing element to the first circumferential location and the second circumferential location and operative contact of the biasing element with the at least one blade lever between the first circumferential location and the second circumferential location provides stability of the biasing element while achieving the advantages described above.

[0008] In another embodiment, a variable turbine geometry assembly for controlling the flow of exhaust gas to a turbine wheel of a turbocharger includes a tuning ring extending along and rotatable about an axis. The variable turbine geometry assembly also includes at least one vane lever coupled to the tuning ring. The at least one vane lever has a first lever end coupled to the tuning ring, a second lever end defining a pin opening, an inner lever surface facing the tuning ring and extending parallel to the tuning ring, and an axial stop extending axially away from the inner lever surface toward the tuning ring and configured to limit axial movement of the at least one vane lever.The variable turbine geometry assembly further includes a pin disposed within the pin opening defined by the second lever end of the at least one lever. The variable turbine geometry assembly further includes at least one vane coupled to the pin, wherein the at least one vane is movable relative to the adjustment ring as the adjustment ring rotates about the axis. The variable turbine geometry assembly further includes a biasing member coupled to the adjustment ring and operatively in contact with the at least one vane lever to bias the at least one vane lever toward the adjustment ring and reduce vibration between the adjustment ring and the at least one vane lever.

[0009] Accordingly, operatively contacting the biasing member with the at least one vane lever to bias the at least one vane lever toward the adjustment ring and reduce vibration between the adjustment ring and the at least one vane lever reduces wear between various components of the variable turbine geometry assembly. More specifically, reduced vibration between the adjustment ring and the at least one vane lever reduces wear on the adjustment ring and the at least one vane lever. Reduced wear on the adjustment ring and the at least one vane lever further reduces noise, vibration, and harshness (NVH) of the turbocharger and lowers the likelihood of a functional failure of the variable turbine geometry assembly that adequately controls the flow of exhaust gas to the turbine wheel of the turbocharger.The fact that the at least one vane lever includes the axial stop extending axially away from the inner lever surface toward the adjustment ring and is configured to limit axial movement of the at least one vane lever further reduces relative distances between the at least one vane lever and the adjustment ring, which allows the biasing element to more easily reduce vibration and thus wear between the at least one vane lever and the adjustment ring.

[0010] In another embodiment, a variable turbine geometry assembly for controlling the flow of exhaust gas to a turbine wheel of a turbocharger includes a tuning ring extending along and rotatable about a first axis. The variable turbine geometry assembly also includes at least one vane lever coupled to the tuning ring and at least one vane coupled to the at least one vane lever. The at least one vane is movable relative to the tuning ring as the tuning ring rotates about the first axis. The at least one vane has a first vane surface facing the first axis and a second vane surface opposite the first vane surface and facing away from the first axis.The at least one blade further has a third blade surface facing the adjustment ring and a fourth blade surface opposite the third blade surface and facing away from the adjustment ring. The first blade surface of the at least one blade has a discontinuous region. The discontinuous region extends along a second axis from a first region end to a second region end spaced from the first region end along the second axis. The second axis is angled obliquely relative to the first axis to transfer an aerodynamic load to the at least one blade.

[0011] Accordingly, the aerodynamic load transferred to the at least one blade through the discontinuous region biases the at least one blade in a particular rotational direction to reduce flutter of the at least one blade. Reduced flutter of the at least one blade reduces vibration between the at least one blade and the at least one blade lever and the timing ring, which in turn reduces wear between various components of the variable geometry turbine assembly. More specifically, reduced vibration between the at least one blade and the at least one blade lever and the timing ring reduces wear on the at least one blade, the at least one blade lever, and the timing ring.Reduced wear on the at least one vane, the at least one vane lever and the adjusting ring further reduces noise, vibration and harshness (NVH) of the turbocharger and reduces the likelihood of functional failure of the variable turbine geometry assembly, which adequately controls the flow of exhaust gas to the turbine wheel of the turbocharger. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Other advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings, in which: Fig. 1 is a cross-sectional view of a turbocharger including a turbine housing defining a turbine housing interior, a turbine wheel disposed within the turbine housing interior, a variable turbine geometry assembly disposed around the turbine wheel, a shaft rotatably coupled to the turbine wheel, a compressor housing defining a compressor housing interior, and a compressor wheel disposed within the compressor housing interior and rotatably coupled to the shaft, Fig. 2 is a perspective view of the variable turbine geometry assembly according to one embodiment, the variable turbine geometry assembly including an adjustment ring, at least one blade lever, at least one blade, and a biasing member, Fig. 3 a cross-sectional view of the adjusting ring, the at least one blade lever, the at least one blade and the preloading element, wherein the at least one blade lever includes an axial stop, and Fig. 4 is a perspective view, partially in phantom, of the at least one blade, wherein the at least one blade has a discontinuous region. DETAILED DESCRIPTION OF THE INVENTION

[0013] Referring to the figures, wherein like numerals indicate like parts throughout the several views, a variable turbine geometry assembly 10 for controlling the flow of exhaust gas to a turbine wheel 12 of a turbocharger 14 is shown in Fig. 1 and Fig. 2. The variable turbine geometry assembly 10 includes an adjustment ring 16 extending along and rotatable about an axis A1. The variable turbine geometry assembly 10 also includes at least one vane lever 18 coupled to the adjustment ring 16, and the variable turbine geometry assembly 10 includes at least one vane 20 coupled to the at least one vane lever 18. The at least one vane 20 is movable relative to the adjustment ring 16 as the adjustment ring 16 rotates about the axis A1. The variable turbine geometry assembly 10 further includes a biasing member 22 coupled to the adjustment ring 16 at a first circumferential location 24 on the adjustment ring 16 and coupled to the adjustment ring 16 at a second circumferential location 26 different from the first circumferential location 24 on the adjustment ring 16.The biasing element 22 extends from the first circumferential location 24 on the adjustment ring 16 to the second circumferential location 26 on the adjustment ring 16. The biasing element 22 is operatively in contact with the at least one vane lever 18 between the first circumferential location 24 and the second circumferential location 26 to bias the at least one vane lever 18 toward the adjustment ring 16 and reduce vibration between the adjustment ring 16 and the at least one vane lever 18.

[0014] Accordingly, operative contact of the biasing member 22 with the at least one vane lever 18 to bias the at least one vane lever 18 toward the adjustment ring 16 and reduce vibration between the adjustment ring 16 and the at least one vane lever 18 reduces wear between various components of the variable turbine geometry assembly 10. More specifically, reduced vibration between the adjustment ring 16 and the at least one vane lever 18 reduces wear on the adjustment ring 16 and on the at least one vane lever 18. Reduced wear on the adjustment ring 16 and the at least one vane lever 18 further reduces noise, vibration, and harshness (NVH) of the turbocharger 14 and lowers the likelihood of a functional failure of the variable turbine geometry assembly 10 that adequately controls the flow of exhaust gas to the turbine wheel 12 of the turbocharger 14.Furthermore, coupling the biasing element 22 to the first circumferential location 24 and the second circumferential location 26 and operatively contacting the biasing element 22 with the at least one blade lever 18 between the first circumferential location 24 and the second circumferential location 26 provides stability for the biasing element 22 while achieving the advantages described above.

[0015] The prestressing element 22 may be in direct contact with the at least one blade lever 18, as in Fig. 2. However, it should be understood that the biasing element 22 does not need to be in direct contact with the at least one vane lever 18. The biasing element 22 only needs to be in operative contact with the at least one vane lever 18. As such, an additional component(s) disposed between the biasing element 22 and the at least one vane lever 18 may be included, as long as the biasing element 22 is capable of biasing the at least one vane lever 18 toward the adjustment ring 16. Even in embodiments in which an additional component(s) is (are) disposed between the biasing element 22 and the at least one vane lever 18, vibration between the adjustment ring 16 and the at least one vane lever 18 is reduced.

[0016] Although not required, as in Fig. 2, the biasing member 22 may extend circumferentially from the first circumferential location 24 to the second circumferential location 26 around a majority of the adjustment ring 16. The biasing member may be generally C-shaped. Extending the biasing member 22 circumferentially around a majority of the adjustment ring 16 increases the stability of the biasing member 22 and allows the biasing member 22 to operatively contact more than one vane 20. Alternatively, the biasing member 22 may extend from the first circumferential location 24 to the second circumferential location 26 around only a small portion of the adjustment ring 16. In one non-limiting example, the first circumferential location 24 may be circumferentially spaced from the second circumferential location 26 such that only one vane lever 18 is disposed between the first circumferential location 24 and the second circumferential location 26.In another non-limiting example, the first circumferential location 24 may be circumferentially spaced from the second circumferential location 26 such that two, three, four, five, six, seven, eight or more vane levers 18 are disposed between the first circumferential location 24 and the second circumferential location 26.

[0017] The biasing element 22 may further be defined as a wire spring, as in Fig. 2. However, it should be understood that the biasing element 22 may be, among other things, a coil spring, a flat spring, a serpentine spring, a Belleville spring, a wave spring, or a spring washer.

[0018] The biasing element 22 may include at least one planar portion 28 extending parallel to the adjustment ring 16 and at least one contact portion 30 extending axially away from the at least one planar portion 28 toward the at least one vane lever 18. The at least one contact portion 30 is operatively in contact with the at least one vane lever 18. The at least one contact portion 30 of the biasing element 22 may be in direct contact with the at least one vane lever 18. However, it should be understood that the at least one contact portion 30 of the biasing element 22 does not need to be in direct contact with the at least one vane lever 18. The at least one contact portion 30 of the biasing element 22 only needs to be in operative contact with the at least one vane lever 18.Therefore, an additional component(s) may be included that is (are) arranged between the at least one contact portion 30 of the biasing element 22 and the at least one blade lever 18, as long as the at least one contact portion 30 of the biasing element 22 is capable of biasing the at least one blade lever 18 toward the adjustment ring 16. Even in the embodiments in which an additional component(s) is (are) arranged between the at least one contact portion 30 of the biasing element 22 and the at least one blade lever 18, vibration between the adjustment ring 16 and the at least one blade lever 18 is reduced.

[0019] As in Fig. 2, the at least one contact portion 30 may be disposed between an adjacent pair of planar portions 28. Furthermore, the at least one contact portion 30 may be generally U-shaped. However, it is contemplated that the at least one contact portion 30 may alternatively be V-shaped or I-shaped.

[0020] Although not required, as in Fig. 2, the biasing member 22 may be coupled to the adjustment ring 16 at a third circumferential location 32 on the adjustment ring 16. The biasing member 22 may also be coupled to the adjustment ring 16 at a fourth circumferential location, a fifth circumferential location, or more circumferential locations. Additional circumferential locations at which the biasing member 22 is coupled to the adjustment ring 16 increase the stability of the biasing member 22. Further, it should be understood that the biasing member 22 may be fixed to the adjustment ring 16 at the first circumferential location 24 and the second circumferential location 26. Furthermore, in the embodiments having the third circumferential location 32, the biasing member 22 may be fixed to the adjustment ring 16 at the third circumferential location 32. The biasing member 22 may also be fixed to the adjustment ring 16 at the fourth circumferential location, the fifth circumferential location, or more circumferential locations.

[0021] The at least one blade lever 18 may be further defined as a plurality of blade levers 18. Furthermore, the at least one blade 20 may be further defined as a plurality of blades 20. It should be understood that the biasing member 22 may be operatively in contact with at least two of the blade levers 18. In other words, the biasing member 22 may be operatively in contact with two of the blade levers 18, three of the blade levers 18, four of the blade levers 18, five of the blade levers 18, six of the blade levers 18, seven of the blade levers 18, eight of the blade levers 18, up to all of the blade levers 18 included in the variable geometry turbine assembly 10. Furthermore, the biasing member 22 may be operatively in contact with at least three of the blade levers 18.In other words, the biasing member 22 may be operatively in contact with three of the blade levers 18, four of the blade levers 18, five of the blade levers 18, six of the blade levers 18, seven of the blade levers 18, eight of the blade levers 18, up to all of the blade levers 18 included in the variable turbine geometry assembly 10.

[0022] As in Fig. 2, the variable geometry turbine assembly 10 may further include an adjustment projection 34 coupled to the adjustment ring 16 and extending axially away from the adjustment ring 16. The adjustment projection 34 may be circumferentially disposed between the first circumferential location 24 and the second circumferential location 26. The adjustment projection 34 may be coupled to an actuator configured to move the adjustment projection 34 to rotate the adjustment ring 16 about the axis A1 and move the at least one blade 20.

[0023] The at least one vane lever 18 may have a contact surface 36 facing away from the adjustment ring 16. The biasing element 22 may be operatively in contact with the contact surface 36 of the at least one vane lever 18 to reduce vibration between the adjustment ring 16 and the at least one vane lever 18. The biasing element 22 may be in direct contact with the contact surface 36 of the at least one vane lever 18. However, it should be understood that the biasing element 22 does not need to be in direct contact with the contact surface 36 of the at least one vane lever 18 to be operatively in contact with the contact surface 36. As such, an additional component(s) may be included that is (are) disposed between the biasing element 22 and the contact surface 36 of the at least one vane lever 18.Even in embodiments in which an additional component(s) is (are) arranged between the preload element 22 and the contact surface 36 of the at least one blade lever 18, vibration between the adjustment ring 16 and the at least one blade lever 18 is reduced. Furthermore, although not required, the contact surface 36 of the at least one blade lever 18 can be axially recessed into the at least one blade lever 18 to support the preload element 22. Supporting the preload element 22 further increases the stability of the preload element 22 relative to the adjustment ring 16.

[0024] The biasing member 22 may include at least one planar portion 28 extending parallel to the adjustment ring 16 and at least one contact portion 30 extending axially away from the at least one planar portion 28 toward the at least one vane lever 18. The at least one contact portion 30 of the biasing member 22 may operatively contact the contact surface 36 of the at least one vane lever 18. The at least one contact portion 30 of the biasing member 22 may be in direct contact with the contact surface 36 of the at least one vane lever 18. However, it should be understood that the at least one contact portion 30 of the biasing member 22 need not be in direct contact with the contact surface 36 of the at least one vane lever 18 to be operatively contacted with the contact surface 36.Therefore, an additional component(s) may be included, which is (are) arranged between the at least one contact portion 30 of the biasing element 22 and the contact surface 36 of the at least one blade lever 18. Even in the embodiments in which an additional component(s) is (are) arranged between the at least one contact portion 30 of the biasing element 22 and the contact surface 36 of the at least one blade lever 18, vibration between the adjustment ring 16 and the at least one blade lever 18 is reduced.

[0025] Furthermore, as in Fig. 1, the turbocharger 14 may comprise the variable turbine geometry assembly 10 as shown in Fig. 2. The turbocharger 14 may include a shaft 38 extending along the axis A1 between a first shaft end 40 and a second shaft end 42 spaced from the first shaft end 40 along the axis A1. The turbocharger 14 may also include the turbine wheel 12 coupled to the first shaft end 40 of the shaft 38 and a compressor wheel 44 coupled to the second shaft end 42 of the shaft 38. The turbocharger 14 may further include a turbine housing 46 defining a turbine housing interior 48, with the turbine wheel 12 disposed within the turbine housing interior 48, and a compressor housing 50 defining a compressor housing interior 52, with the compressor wheel 44 disposed within the compressor housing interior 52.

[0026] In another embodiment, as in Fig. 3, the variable turbine geometry assembly 10 includes the adjustment ring 16 extending along and rotatable about the axis A1. The variable turbine geometry assembly 10 also includes at least one blade lever 18 coupled to the adjustment ring 16. In the embodiment shown in Fig. 3, the at least one blade lever 18 has a first lever end 54 coupled to the adjustment ring 16, a second lever end 56 defining a pin opening 58, an inner lever surface 60 facing the adjustment ring 16 and extending parallel to the adjustment ring 16, and an axial stop 62 extending axially away from the inner lever surface 60 toward the adjustment ring 16 and configured to limit axial movement of the at least one blade lever 18. Although not required, the first lever end 54 may be fixed to the adjustment ring 16. The variable turbine geometry assembly 10 in the embodiment as shown in Fig. 3, further includes a pin 64 disposed within the pin opening 58 defined by the second lever end 56 of the at least one vane lever 18. Although not required, the second lever end 56 may be fixed to the pin 64. The variable turbine geometry assembly 10 further includes at least one vane 20 coupled to the pin 64, the at least one vane 20 being movable relative to the adjustment ring 16 as the adjustment ring 16 rotates about the axis A1. The variable turbine geometry assembly 10 further includes the biasing member 22 coupled to the adjustment ring 16 and operatively in contact with the at least one vane lever 18 to bias the at least one vane lever 18 toward the adjustment ring 16 and reduce vibration between the adjustment ring 16 and the at least one vane lever 18.

[0027] Accordingly, operative contact of the biasing member 22 with the at least one vane lever 18 to bias the at least one vane lever 18 toward the adjustment ring 16 and reduce vibration between the adjustment ring 16 and the at least one vane lever 18 reduces wear between various components of the variable turbine geometry assembly 10. More specifically, reduced vibration between the adjustment ring 16 and the at least one vane lever 18 reduces wear on the adjustment ring 16 and on the at least one vane lever 18. Reduced wear on the adjustment ring 16 and the at least one vane lever 18 further reduces noise, vibration, and harshness (NVH) of the turbocharger 14 and lowers the likelihood of a functional failure of the variable turbine geometry assembly 10 that adequately controls the flow of exhaust gas to the turbine wheel 12 of the turbocharger 14.The fact that the at least one vane lever 18 includes the axial stop 62, which extends axially away from the inner lever surface 60 toward the adjustment ring 16 and is configured to limit axial movement of the at least one vane lever 18, further reduces relative distances between the at least one vane lever 18 and the adjustment ring 16, which allows the biasing element 22 to more easily reduce vibration and thus wear between the at least one vane lever 18 and the adjustment ring 16. Although not required, the axial stop 62 may have a first stop surface 66 facing the adjustment ring 16, a second stop surface 68 facing the axis A1, and a third stop surface 70 opposite the first stop surface 66 facing away from the axis A1.

[0028] It is to be understood that in the embodiment as in Fig. 3, the prestressing element 22 is not on prestressing element 22, as in Fig. 2. In one non-limiting example, the biasing member 22 may be two or more biasing members 22, each of which is operatively in contact with the at least one vane lever 18 to bias the at least one vane lever 18 toward the adjustment ring 16 and reduce vibration between the adjustment ring 16 and the at least one vane lever 18.

[0029] However, it should also be understood that the prestressing element 22, as in Fig. 2, the same preload element 22 as in Fig. 3 and as described herein. As such, although not required, the biasing member 22 may be coupled to the adjustment ring 16 at the first circumferential location 24 on the adjustment ring 16 and may be coupled to the adjustment ring 16 at the second circumferential location 26, which is different from the first circumferential location 24 on the adjustment ring 16. In this embodiment, the biasing member 22 extends from the first circumferential location 24 on the adjustment ring 16 to the second circumferential location 26 on the adjustment ring 16. The biasing member 22 may be operatively in contact with the at least one vane lever 18 between the first circumferential location 24 and the second circumferential location 26 to bias the at least one vane lever 18 toward the adjustment ring 16 and reduce vibration between the adjustment ring 16 and the at least one vane lever 18.

[0030] Furthermore, the biasing element 22 in the embodiment as shown in Fig. 3, be in direct contact with the at least one vane lever 18. However, it should be understood that the biasing element 22 does not need to be in direct contact with the at least one vane lever 18. The biasing element 22 only needs to be in operative contact with the at least one vane lever 18. As such, an additional component(s) disposed between the biasing element 22 and the at least one vane lever 18 may be included, as long as the biasing element 22 is capable of biasing the at least one vane lever 18 toward the adjustment ring 16. Even in the embodiments in which an additional component(s) is (are) disposed between the biasing element 22 and the at least one vane lever 18, vibration between the adjustment ring 16 and the at least one vane lever 18 is reduced.

[0031] Although not required, the biasing element 22 may also be in the embodiment as shown in Fig. 3, extend circumferentially from the first circumferential location 24 to the second circumferential location 26 around a majority of the adjustment ring 16. The biasing member may be generally C-shaped. Extending the biasing member 22 circumferentially around a majority of the adjustment ring 16 increases the stability of the biasing member 22 and allows the biasing member 22 to operatively contact more than one vane 20. Alternatively, the biasing member 22 may extend from the first circumferential location 24 to the second circumferential location 26 around only a small portion of the adjustment ring 16. In one non-limiting example, the first circumferential location 24 may be circumferentially spaced from the second circumferential location 26 such that only one vane lever 18 is disposed between the first circumferential location 24 and the second circumferential location 26.In another non-limiting example, the first circumferential location 24 may be circumferentially spaced from the second circumferential location 26 such that two, three, four, five, six, seven, eight or more vane levers 18 are disposed between the first circumferential location 24 and the second circumferential location 26.

[0032] The preloading element 22, as in Fig. 3, may be further defined as the wire spring. However, it should be understood that the biasing element 22 may be, among others, the coil spring, the flat spring, the serpentine spring, the Belleville spring, the wave spring, or the spring washer.

[0033] Furthermore, the biasing element 22 in the embodiment as shown in Fig. 3, at least one planar portion 28 extending parallel to the adjustment ring 16 and at least one contact portion 30 extending axially away from the at least one planar portion 28 toward the at least one vane lever 18. The at least one contact portion 30 is operatively in contact with the at least one vane lever 18. The at least one contact portion 30 of the biasing member 22 may be in direct contact with the at least one vane lever 18. However, it should be understood that the at least one contact portion 30 of the biasing member 22 does not need to be in direct contact with the at least one vane lever 18. The at least one contact portion 30 of the biasing member 22 only needs to be in operative contact with the at least one vane lever 18.Therefore, an additional component(s) may be included that is (are) arranged between the at least one contact portion 30 of the biasing element 22 and the at least one blade lever 18, as long as the at least one contact portion 30 of the biasing element 22 is capable of biasing the at least one blade lever 18 toward the adjustment ring 16. Even in the embodiments in which an additional component(s) is (are) arranged between the at least one contact portion 30 of the biasing element 22 and the at least one blade lever 18, vibration between the adjustment ring 16 and the at least one blade lever 18 is reduced.

[0034] Furthermore, the at least one contact section 30 in the embodiment as shown in Fig. 3, between an adjacent pair of planar portions 28. Furthermore, the at least one contact portion 30 may be generally U-shaped. However, it is contemplated that the at least one contact portion 30 may alternatively be V-shaped or I-shaped.

[0035] Although not required, the biasing element 22 in the embodiment as shown in Fig. 3, the biasing member 22 may be coupled to the adjustment ring 16 at the third circumferential location 32 on the adjustment ring 16. The biasing member 22 may also be coupled to the adjustment ring 16 at the fourth circumferential location, the fifth circumferential location, or more circumferential locations. Additional circumferential locations at which the biasing member 22 is coupled to the adjustment ring 16 increase the stability of the biasing member 22. Further, it should be understood that the biasing member 22 may be fixed to the adjustment ring 16 at the first circumferential location 24 and the second circumferential location 26. Furthermore, in the embodiments having the third circumferential location 32, the biasing member 22 may be fixed to the adjustment ring 16 at the third circumferential location 32. The biasing member 22 may also be fixed to the adjustment ring 16 at the fourth circumferential location, the fifth circumferential location, or more circumferential locations.

[0036] In the embodiment as in Fig. 3, the at least one blade lever 18 may also be further defined as the plurality of blade levers 18. Furthermore, the at least one blade 20 may be further defined as the plurality of blades 20. It should be understood that the biasing element 22 of the embodiment as shown in Fig. 3, the biasing member 22 may be operatively in contact with at least two of the vane levers 18. In other words, the biasing member 22 may be operatively in contact with two of the vane levers 18, three of the vane levers 18, four of the vane levers 18, five of the vane levers 18, six of the vane levers 18, seven of the vane levers 18, eight of the vane levers 18, up to all of the vane levers 18 included in the variable turbine geometry assembly 10. Furthermore, the biasing member 22 may be operatively in contact with at least three of the vane levers 18. In other words, the biasing member 22 may be operatively in contact with three of the blade levers 18, four of the blade levers 18, five of the blade levers 18, six of the blade levers 18, seven of the blade levers 18, eight of the blade levers 18, up to all of the blade levers 18 included in the variable turbine geometry assembly 10.

[0037] Although not in Fig. 3, it is to be understood that the variable turbine geometry assembly 10 of the embodiment as shown in Fig. 3, may further include an adjustment projection 34 coupled to the adjustment ring 16 and extending axially away from the adjustment ring 16. The adjustment projection 34 may be circumferentially disposed between the first circumferential location 24 and the second circumferential location 26. The adjustment projection 34 may be coupled to an actuator configured to move the adjustment projection 34 to rotate the adjustment ring 16 about the axis A1 and move the at least one blade 20.

[0038] Furthermore, the at least one blade lever 18 of the embodiment, as shown in Fig. 3, having the contact surface 36 facing away from the adjustment ring 16. The biasing member 22 may be operatively in contact with the contact surface 36 of the at least one vane lever 18 to reduce vibration between the adjustment ring 16 and the at least one vane lever 18. The biasing member 22 may be in direct contact with the contact surface 36 of the at least one vane lever 18. However, it should be understood that the biasing member 22 need not be in direct contact with the contact surface 36 of the at least one vane lever 18 to be operatively in contact with the contact surface 36. As such, an additional component(s) may be included that is (are) disposed between the biasing member 22 and the contact surface 36 of the at least one vane lever 18.Even in the embodiments in which an additional component(s) is (are) arranged between the biasing element 22 and the contact surface 36 of the at least one blade lever 18, vibration between the adjusting ring 16 and the at least one blade lever 18 is reduced. Although not required, the contact surface 36 of the at least one blade lever 18 can also be provided in the embodiment as shown in FIG. Fig. 3, be axially recessed into the at least one blade lever 18 in order to support the preloading element 22. Supporting the preloading element 22 further increases the stability of the preloading element 22 relative to the adjusting ring 16.

[0039] Furthermore, it is to be understood that the biasing element 22 of the embodiment as shown in Fig. 3, at least one planar portion 28 extending parallel to the adjustment ring 16 and at least one contact portion 30 extending axially away from the at least one planar portion 28 toward the at least one vane lever 18. The at least one contact portion 30 of the biasing member 22 may operatively contact the contact surface 36 of the at least one vane lever 18. The at least one contact portion 30 of the biasing member 22 may be in direct contact with the contact surface 36 of the at least one vane lever 18. However, it should be understood that the at least one contact portion 30 of the biasing member 22 need not be in direct contact with the contact surface 36 of the at least one vane lever 18 to be operatively contacted with the contact surface 36.Therefore, an additional component(s) may be included, which is (are) arranged between the at least one contact portion 30 of the biasing element 22 and the contact surface 36 of the at least one blade lever 18. Even in the embodiments in which an additional component(s) is (are) arranged between the at least one contact portion 30 of the biasing element 22 and the contact surface 36 of the at least one blade lever 18, vibration between the adjustment ring 16 and the at least one blade lever 18 is reduced.

[0040] Furthermore, as in Fig. 1, the turbocharger 14 may comprise the variable turbine geometry assembly 10 as shown in Fig. 3. The turbocharger 14 may include the shaft 38 extending along the axis A1 between the first shaft end 40 and the second shaft end 42 spaced from the first shaft end 40 along the axis A1. The turbocharger 14 may also include the turbine wheel 12 coupled to the first shaft end 40 of the shaft 38 and the compressor wheel 44 coupled to the second shaft end 42 of the shaft 38. The turbocharger 14 may further include the turbine housing 46 defining the turbine housing interior 48, with the turbine wheel 12 disposed within the turbine housing interior 48, and the compressor housing 50 defining the compressor housing interior 52, with the compressor wheel 44 disposed within the compressor housing interior 52.

[0041] In another embodiment, as in Fig. 4, the variable turbine geometry assembly 10 includes the adjustment ring 16 extending along and rotatable about the first axis A1. The variable turbine geometry assembly 10 also includes at least one vane lever 18 coupled to the adjustment ring 16, and the variable turbine geometry assembly 10 includes at least one vane 20 coupled to the at least one vane lever 18. The at least one vane 20 is movable with respect to the adjustment ring 16 as the adjustment ring 16 rotates about the first axis A1. The at least one vane 20 has a first vane surface 72 facing the first axis A1 and a second vane surface 74 opposite the first vane surface 72 and facing away from the first axis A1.The at least one blade 20 further has a third blade surface 76 facing the adjustment ring 16 and a fourth blade surface 78 opposite the third blade surface 76 and facing away from the adjustment ring 16. The first blade surface 72 of the at least one blade 20 has a discontinuous region 80. The discontinuous region 80 extends along a second axis A2 from a first region end 82 to a second region end 84 spaced from the first region end 82 along the second axis A2. The second axis A2 is angled obliquely relative to the first axis A1 to transfer an aerodynamic load to the at least one blade 20.

[0042] Accordingly, the aerodynamic load transferred to the at least one blade 20 through the discontinuous region 80 biases the at least one blade 20 in a particular rotational direction to reduce flutter of the at least one blade 20. Reduced flutter of the at least one blade 20 reduces vibration between the at least one blade 20 and the at least one blade lever 18 and the adjustment ring 16, which in turn reduces wear between various components of the variable turbine geometry assembly 10. More specifically, reduced vibration between the at least one blade 20 and the at least one blade lever 18 and the adjustment ring 16 reduces wear on the at least one blade 20, the at least one blade lever 18, and the adjustment ring 16.Reduced wear on the at least one vane 20, the at least one vane lever 18, and the adjustment ring 16 further reduces noise, vibration, and harshness (NVH) of the turbocharger 14 and reduces the likelihood of a functional failure of the variable turbine geometry assembly 10 that adequately controls the flow of exhaust gas to the turbine wheel 12 of the turbocharger 14.

[0043] Although not required, the first region end 82 may be axially offset from the second region end 84 such that the first region end 82 is spaced from the second region end 84 along the first axis A1. Further, it should be understood that the discontinuous region 80 may extend away from the first blade surface 72 of the at least one blade 20. In other words, the discontinuous region 80 may be a protrusion such as a rib. Alternatively, it should be understood that the discontinuous region 80 may be indented into the first blade surface 72 of the at least one blade 20. In other words, the discontinuous region 80 may be a groove, a channel, or other void space. It is also to be understood that the discontinuous region 80 may include a portion(s) extending away from the first blade surface 72 (i.e., a protrusion(s) such asa rib, while the discontinuous region 80 may also include a portion that is (are) indented into the first blade surface 72 (ie, a groove, a channel, or other void space).

[0044] Although not required, it is to be understood that the at least one blade 20 of the embodiment as shown in Fig. 4, in combination with the variable turbine geometry assembly 10, as shown in Fig. 2, and the variable turbine geometry assembly 10, as shown in Fig. 3 shown, can be used.

Claims

[1] A variable turbine geometry assembly (10) for controlling the flow of exhaust gas to a turbine wheel (12) of a turbocharger (14), the variable turbine geometry assembly (10) comprising: an adjusting ring (16) extending along an axis (A1) and rotatable about it, at least one blade lever (18) coupled to the adjusting ring (16), at least one blade (20) coupled to the at least one blade lever (18), wherein the at least one blade (20) is movable relative to the adjusting ring (16) when the adjusting ring (16) rotates about the axis (A1), and a prestressing element (22), which is coupled to the adjusting ring (16) at a first circumferential location (24) on the adjusting ring (16), which is coupled to the adjusting ring (16) at a second circumferential location (26) which is different from the first circumferential location on the adjusting ring (16), which extends from the first circumferential point (24) on the adjusting ring (16) to the second circumferential point (26) on the adjusting ring (16) and which is operatively in contact with the at least one blade lever (18) between the first circumferential location (24) and the second circumferential location (26) to bias the at least one blade lever (18) towards the adjusting ring (16) and To reduce vibration between the adjusting ring (16) and the at least one blade lever (18). [2] Variable geometry turbine assembly (10) according to claim 1, wherein the biasing element (22) is in direct contact with the at least one blade lever (18). [3] The variable geometry turbine assembly (10) of any of claims 1-2, wherein the biasing member (22) extends circumferentially around a majority of the adjusting ring (16) from the first circumferential location (24) to the second circumferential location (26). [4] The variable geometry turbine assembly (10) of any of claims 1-3, wherein the biasing member (22) includes at least one planar portion (28) extending parallel to the adjustment ring (16) and at least one contact portion (30) extending axially away from the at least one planar portion (28) toward the at least one blade lever (18), the at least one contact portion (30) being operatively in contact with the at least one blade lever (18). [5] A variable geometry turbine assembly (10) according to any one of claims 1-4, wherein the at least one contact portion (30) is disposed between an adjacent pair of planar portions (28). [6] A variable geometry turbine assembly (10) according to any one of claims 1-5, wherein the at least one contact portion (30) is generally U-shaped. [7] The variable geometry turbine assembly (10) of any of claims 1-6, wherein the biasing member (22) is coupled to the adjustment ring (16) at a third circumferential location (32) on the adjustment ring (16). [8] The variable geometry turbine assembly (10) of any of claims 1-7, wherein the at least one vane lever (18) is further defined as a plurality of vane levers (18), wherein the at least one vane (20) is further defined as a plurality of vanes (20), and wherein the biasing member (22) is operatively in contact with at least two of the vane levers (18). [9] A variable geometry turbine assembly according to any one of claims 1-8, wherein the biasing element (22) is further defined as a wire spring. [10] A turbocharger (14) comprising the variable turbine geometry assembly (10) according to any one of claims 1-9 and further comprising: a shaft (38) extending along the axis (A1) between a first shaft end (40) and a second shaft end (42) spaced from the first shaft end (40) along the axis (A1), a turbine wheel (12) coupled to the first shaft end (40) of the shaft (38), a compressor wheel (44) coupled to the second shaft end (42) of the shaft (38), and a turbine housing (46) defining a turbine housing interior (48), wherein the turbine wheel (12) is arranged in the turbine housing interior (48).

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