Exhaust turbocharger

Patent metadata

Field	Value
Publication number	US-9759125-B2
Application number	US-201414895553-A
Country	US
Kind code	B2
Filing date	Jun 2, 2014
Priority date	Jun 4, 2013
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

An internal combustion engine ( 20 ) has two exhaust valves ( 24, 25 ) for each combustion chamber, to permit separation of blow-down and expulsion phases of an exhaust stroke. The separate exhaust streams are directed to different geometries of an exhaust turbocharger ( 30 ), so as to make best use thereof. Variable exhaust valve timing, and bypass passage for the exhaust streams are disclosed.

First claim

The invention claimed is:

1. A method of operating an internal combustion engine and exhaust turbocharger in combination, said engine having a combustion chamber with first and second exhaust orts, the first exhaust port having a first exhaust valve for controlling flow of exhaust gas through the first exhaust port and the second exhaust port having a second exhaust valve for controlling flow of exhaust gas through the second exhaust port, wherein the first and second exhaust ports are coupled via respective first and second exhaust tracts to respective first and second turbine inlets of said exhaust turbocharger, wherein turbine geometries associated with said first and second exhaust tracts are distinct, the method comprising:
controlling at least one of a cam shaft and a variable valve timing system to separate exhaust blow-down and exhaust expulsion phases of an exhaust stroke of the engine;
directing gas exhausted from the combustion chamber during said blow-down chase of said exhaust stroke to a first of the distinct turbine geometries via the first turbine inlet and the first exhaust port; and
directing gas exhausted from the combustion chamber during said expulsion phase of said exhaust stroke to a second of the distinct turbine geometries via the second turbine inlet and the second exhaust port.

2. The method of claim 1 , including varying the timing of the exhaust valves according to engine speed and load, to vary a proportion of exhaust gas directed to said different geometries.

3. The method of claim 2 , including diverting to a downstream exhaust side of a turbine wheel of said turbocharger a proportion of exhaust gas from one or both said phases.

4. A system, comprising;
an internal combustion engine and an exhaust-driven turbine, said engine having a combustion chamber with first and second exhaust ports, the first exhaust port having a first exhaust valve for controlling flow of exhaust gas through the first exhaust port and the second exhaust port having a second exhaust valve for controlling flow of exhaust gas through the second exhaust port, wherein the first and second exhaust ports are coupled via respective first and second exhaust tracts to respective first and second turbine inlets of said exhaust-driven turbine, wherein turbine geometries associated with said first and second exhaust tracts are distinct,
wherein an electronic control unit (ECU) is configured to control at least one of a cam shaft and a variable valve timing system to separate exhaust blow-down and exhaust expulsion phases of an exhaust stroke by:
directing gas exhausted from the combustion chamber during said exhaust blow-down phase of said exhaust stroke to a first turbine geometry of the distinct turbine geometries via the first turbine inlet and the first exhaust port, and
directing gas exhausted from the combustion chamber during said expulsion phase of said exhaust stroke to a second turbine geometry of the distinct turbine geometries via the second turbine inlet and the second exhaust port.

5. A system, comprising:
an internal combustion engine;
an exhaust turbocharger, said engine having a combustion chamber with first and second exhaust ports, the first exhaust port having a first exhaust valve for controlling flow of exhaust gas through the first exhaust port and the second exhaust port having a second exhaust valve for controlling flow of exhaust gas through the second exhaust port, wherein the first and second exhaust ports are coupled via respective first and second exhaust tracts to respective first and second turbine inlets of said exhaust turbocharger, wherein turbine geometries associated with said first and second exhaust tracts are distinct; and
an electronic control unit (ECU) configured to control at least one of a cam shaft and a variable valve timing system to separate exhaust blow-down and exhaust expulsion phases of an exhaust stroke by:
directing gas exhausted from the combustion chamber during said exhaust blow-down phase of said exhaust stroke to a first turbine geometry of the distinct turbine geometries via the first turbine inlet and the first exhaust port, and
directing gas exhausted from the combustion chamber during said expulsion phase of said exhaust stroke to a second turbine geometry of the distinct turbine geometries via the second turbine inlet and the second exhaust port.

6. The system as claimed in claim 5 , wherein vanes of the turbine wheel are arcuate.

7. The system as claimed in claim 5 , wherein one of said first and second turbine inlets comprises a nozzle.

8. The system as claimed in claim 7 , wherein the first and second turbine inlets comprise respective nozzles.

9. The system as claimed in claim 8 , wherein an outlet direction of the nozzle associated with the first turbine inlet is non-parallel to an outlet direction of the nozzle associated with the second turbine inlet.

10. The system as claimed in claim 7 , wherein one of said nozzles comprises an actuator controllable to vary the outlet direction of the one of said nozzles.

11. The system as claimed in claim 5 , wherein one of said first and second turbine inlets includes a stator having one or more vanes to direct an exhaust stream.

12. The system as claimed in claim 11 , wherein the first and second turbine inlets each comprise a respective stator.

13. The system as claimed in claim 11 , wherein the stator is movable to change a direction of an exhaust stream.

14. The system as claimed in claim 5 , wherein the ECU is configured to change an opening duration of at least one of said first and second exhaust valves.

15. The system as claimed in claim 5 , wherein the ECU is configured to change an opening area of at least one of said first and second exhaust valves.

16. The system as claimed in claim 5 , wherein the ECU is configured to vary a timing of opening and/or closing of one or more of said first and second exhaust valves with respect to the rotation of an output member of said engine.

17. The system as claimed in claim 5 , wherein one of said exhaust tracts includes a diverter valve having an inlet from said engine and an outlet for connection to a downstream exhaust side of a turbine wheel of said turbocharger.

18. The system as claimed in claim 17 , wherein said diverter valve has an inlet from said engine, a first outlet to said turbocharger, and a second outlet for connection to a bypass of a turbine wheel of said turbocharger.

19. The system as claimed in claim 5 , wherein both said exhaust tracts includes a diverter valve, each diverter valve having an inlet from said engine and an outlet for connection to a downstream exhaust side of a turbine wheel of said turbocharger.

20. The system as claimed in claim 5 , wherein said engine has multiple cylinders.

21. The system as claimed in claim 20 , wherein said engine has four cylinders in line.

22. A vehicle incorporating the system of claim 5 .

Assignees

• Jaguar Land Rover Ltd

Inventors

• Baker Alan
• Turner James

Classifications

• F02B37/12

  Control of the pumps · CPC title

• F02B37/025 Primary

  Multiple scrolls or multiple gas passages guiding the gas to the pump drive · CPC title

• F02D13/0249

  changing the valve timing only · CPC title

• F02B33/34

  with rotary pumps (with cell-type pressure exchangers or the like F02B33/42) · CPC title

• F02D2041/001

  for engines with variable valve actuation · CPC title