Granted Patent B2

US 10,047,760 · App. 14/555,569 · Granted Aug 14, 2018

Abstract

Claims (28)

1. An assembly comprising:

a turbine housing that defines an inlet, a bore, a volute, a wastegate opening, a passage to one side of the wastegate opening that extends in a direction of flow from the inlet to the volute, and a chamber to another side of the wastegate opening, wherein the turbine housing comprises a wastegate seat disposed about the wastegate opening, wherein the wastegate seat and the wastegate opening meet at a perimeter of the wastegate opening that comprises an upstream toe end and a downstream back end oriented in the direction of flow from the inlet to the volute, and wherein the downstream back end of the perimeter of the wastegate opening comprises a radius of curvature that exceeds a radius of curvature of the upstream toe end of the perimeter of the wastegate opening;

a rotatable wastegate shaft configured for receipt by the bore;

a wastegate arm that extends from the rotatable wastegate shaft; and

a wastegate plug that extends from the wastegate arm, wherein the wastegate plug comprises a seal surface that comprises a toe end and a back end,

wherein, responsive to rotation of the rotatable wastegate shaft in the bore, the wastegate plug transitions the wastegate opening from a closed state to an open state,

wherein, in the closed state, the seal surface of the wastegate plug contacts the wastegate seat, and

wherein, in the open state, the toe end of the seal surface of the wastegate plug defines an upstream toe end clearance with respect to the wastegage seat at the upstream toe end perimeter and the back end of the seal surface of the wastegate plug defines a downstream back end clearance with respect to the wastegate seat at the downstream back end perimeter, wherein the defined upstream toe end clearance exceeds the defined downstream back end clearance.

2. The assembly of claim 1 wherein the wastegate plug comprises an elevated portion that extends axially upwardly from the seal surface toward the wastegate arm.

3. The assembly of claim 1 wherein the wastegate plug comprises an elevated portion that extends axially downwardly from the seal surface.

4. The assembly of claim 1 wherein the wastegate seat is disposed about the wastegate opening facing the passage.

5. The assembly of claim 1 wherein the wastegate seat is disposed about the wastegate opening facing the chamber.

6. The assembly of claim 1 wherein the seal surface comprises a perimeter defined by a radiused portion of the toe end of the seal surface and a radiused portion of the back end of the seal surface.

7. The assembly of claim 6 wherein the perimeter is defined by at least one straight portion that extends between the radiused portion of the toe end of the seal surface and the radiused portion of the back end of the seal surface.

8. The assembly of claim 6 wherein the perimeter is defined by at least one curved portion that extends between the radiused portion of the toe end of the seal surface and the radiused portion of the back end of the seal surface.

9. The assembly of claim 8 wherein the perimeter is defined by at least two curved portions that extend between the radiused portion of the toe end of the seal surface and the radiused portion of the back end of the seal surface.

10. The assembly of claim 1 wherein the perimeter of the wastegate opening is defined by at least one straight line that extends between the radius of curvature of the upstream toe end of the perimeter and the radius of curvature of the downstream back end of the perimeter or wherein the perimeter of the wastegate opening is defined by at least one straight line and at least one curved line that extend at least in part between the radius of curvature of the upstream toe end of the perimeter and the radius of curvature of the downstream back end of the perimeter.

11. A turbocharger comprising:

a compressor assembly;

a center housing assembly; and

a turbine assembly that comprises

a turbine housing that defines an inlet, a bore, a volute, a wastegate opening, a passage to one side of the wastegate opening that extends in a direction of flow from the inlet to the volute, and a chamber to another side of the wastegate opening, wherein the turbine housing comprises a wastegate seat disposed about the wastegate opening, wherein the wastegate seat and the wastegate opening meet at a perimeter of the wastegate opening that comprises an upstream toe end and a downstream back end oriented in the direction of flow from the inlet to the volute, and wherein the downstream back end of the perimeter of the wastegate opening comprises a radius of curvature that exceeds a radius of curvature of the upstream toe end of the perimeter of the wastegate opening;

a rotatable wastegate shaft configured for receipt by the bore;

a wastegate arm that extends from the rotatable wastegate shaft; and

a wastegate plug that extends from the wastegate arm, wherein the wastegate plug comprises a seal surface that comprises a toe end and a back end,

wherein, responsive to rotation of the rotatable wastegate shaft in the bore, the wastegate plug transitions the wastegate opening from a closed state to an open state,

wherein, in the closed state, the seal surface of the wastegate plug contacts the wastegate seat, and

wherein, in the open state, the toe end of the seal surface of the wastegate plug defines an upstream toe end clearance with respect to the wastegate seat at the toe end perimeter and the back end of the seal surface of the wastegate plug defines a downstream back end clearance with respect to the wastegate seat at the back end perimeter, wherein the defined upstream toe end clearance exceeds the defined downstream back end clearance.

Assignments (9)