Variable-geometry turbine housing intake channel for an exhaust driven turbocharger

Patent metadata

Field	Value
Publication number	US-10570759-B2
Application number	US-201715645695-A
Country	US
Kind code	B2
Filing date	Jul 10, 2017
Priority date	Jul 10, 2017
Publication date	Feb 25, 2020
Grant date	Feb 25, 2020

Abstract

A variable-geometry turbocharger (VGT) for an internal combustion engine configured to generate a flow of post-combustion gases as a byproduct of generating output torque includes a turbine housing defining a volute. The VGT also includes a turbine wheel mounted on a shaft having a rotational axis, retained inside the turbine housing, and configured to be rotated about the rotational axis by the flow of post-combustion gases. The turbine housing defines an inlet to the turbine wheel downstream of the volute and upstream of the turbine wheel. The inlet to the turbine wheel includes a circumferentially continuous and unobstructed intake channel having a selectable cross-sectional area and configured to regulate effective expansion ratio of the VGT. An internal combustion engine employing such a VGT is also disclosed.

First claim

What is claimed is:

1. A variable-geometry turbocharger (VGT) for an internal combustion engine configured to generate a flow of post-combustion gases as a byproduct of generating output torque, the VGT comprising:
a turbine housing defining a volute; and
a turbine wheel mounted on a shaft having a rotational axis, retained inside the turbine housing, and configured to be rotated about the rotational axis by the flow of post-combustion gases;
wherein:
the turbine housing defines an inlet to the turbine wheel downstream of the volute and upstream of the turbine wheel; and
the inlet to the turbine wheel includes a circumferentially continuous and unobstructed intake channel having a selectable cross-sectional area and configured to regulate an expansion ratio of the VGT; and

a mechanism configured to select the cross-sectional area of the intake channel;
wherein:
the mechanism includes a ring defined by an outer diameter surface and moveably mounted to the turbine housing in the intake channel; and
the ring is in threaded engagement with the turbine housing and configured to simultaneously rotate and translate relative to the turbine housing to thereby select the cross-sectional area of the intake channel.

2. The VGT of claim 1 , further comprising a bearing housing including at least one bearing configured to support the shaft, and the ring is defined by an outer diameter surface and is mounted between the bearing housing and the turbine wheel.

3. The VGT of claim 1 , wherein the outer diameter surface of the ring has one of a rounded and a beveled edge configured to receive the flow of post-combustion gases from the volute and reduce turbulence in the flow of post-combustion gases.

4. The VGT of claim 1 , wherein the volute of the turbine housing includes an internal cylindrical wall defined by a diameter, and wherein the outer diameter of the surface matches the diameter of the internal cylindrical wall.

5. The VGT of claim 1 , wherein the mechanism additionally includes an actuator configured to selectively vary a position of the ring relative to the turbine housing.

6. The VGT of claim 5 , wherein the actuator is configured to vary the position of the ring in a continuous and step-less motion.

7. The VGT of claim 5 , wherein the mechanism additionally includes a controller having a memory and configured to regulate the actuator.

8. An internal combustion engine comprising:
a cylinder configured to receive an air-fuel mixture for combustion therein;
a reciprocating piston disposed inside the cylinder and configured to generate a flow of post-combustion gases from the cylinder; and
a variable geometry turbocharger (VGT) including:
a turbine housing defining a volute; and
a turbine wheel mounted on a shaft having a rotational axis, retained inside the turbine housing, and configured to be rotated about the rotational axis by the flow of post-combustion gases;
wherein:
the turbine housing defines an inlet to the turbine wheel downstream of the volute and upstream of the turbine wheel; and
the inlet to the turbine wheel includes a circumferentially continuous and unobstructed intake channel having a selectable cross-sectional area and configured to regulate effective expansion ratio of the VGT; and

a mechanism configured to select the cross-sectional area of the intake channel;
where:
the mechanism includes a ring defined by an outer diameter surface and moveably mounted to the turbine housing in the intake channel; and
the ring is in threaded engagement with the turbine housing and configured to simultaneously rotate and translate relative to the turbine housing to thereby select the cross-sectional area of the intake channel.

9. The internal combustion engine of claim 8 , wherein the VGT additionally includes a bearing housing including at least one bearing configured to support the shaft, and the ring is mounted between the bearing housing and the turbine wheel.

10. The internal combustion engine of claim 8 , wherein the outer diameter surface of the ring has one of a rounded and a beveled edge configured to receive the flow of post-combustion gases from the volute and reduce turbulence in the flow of post-combustion gases.

11. The internal combustion engine of claim 8 , wherein the volute of the turbine housing includes an internal cylindrical wall defined by a diameter, and wherein the outer diameter of the surface matches the diameter of the internal cylindrical wall.

12. The internal combustion engine of claim 8 , wherein the mechanism additionally includes an actuator configured to selectively vary a position of the ring relative to the turbine housing.

13. The internal combustion engine of claim 12 , wherein the actuator is configured to vary the position of the ring in a continuous and step-less motion.

14. The internal combustion engine of claim 12 , wherein the mechanism additionally includes a controller having a memory and configured to regulate the actuator.

Assignees

• Gm Global Tech Operations Llc

Inventors

• RACCA Alberto

Classifications

• F01D25/24

  Casings (modified for heating or cooling F01D25/14); Casing parts, e.g. diaphragms, casing fastenings (casings for rotary machines or engines in general F16M {; special arrangements in stators dealing with breaking-off of part of rotor F01D21/045}) · CPC title

• F01D17/143

  the shiftable member being a wall, or part thereof of a radial diffuser · CPC title

• F01D5/048

  Form or construction · CPC title

• F02B37/22 Primary

  by varying cross-section of exhaust passages or air passages {, e.g. by throttling turbine inlets or outlets or by varying effective number of guide conduits} (F02B37/24 takes precedence) · CPC title

• F02B37/24

  by using pumps or turbines with adjustable guide vanes · CPC title