Induction venturi for an exhaust gas recirculation system in an internal combustion engine

• US 6,267,106 B1
• Filed: 11/09/1999
• Issued: 07/31/2001
• Est. Priority Date: 11/09/1999
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Feucht, Dennis D.
• Primary Examiner(s): SOLIS, ERICK R
• Application Number:
  US09/437,023
• Time in Patent Office: 630 Days
• Field of Search: 123/568.17, 606/052
• US Class Current: 123/568.17
• CPC Class Codes: F02B 29/0406 Layout of the intake air cooling or coolant circuit
• CPC Class Codes: F02M 26/04 with a single turbocharger
• CPC Class Codes: F02M 26/19 Means for improving the mixing of air and recirculated exhaust gases, e.g. venturis or multiple openings to the intake system

Abstract

An internal combustion engine includes a combustion air supply; an exhaust manifold; and an induction venturi. The induction venturi includes a combustion air inlet connected and in communication with the combustion air supply, an exhaust gas inlet connected and in communication with the exhaust manifold, and an outlet. A venturi section terminates at a venturi throat and is in communication with the combustion air inlet. An expansion section is positioned between and in communication with the venturi section and the outlet. At least one induction port terminates adjacent the venturi throat and within the expansion section.

Claims

1. An internal combustion engine, comprising:

a combustion air supply;

an exhaust manifold; and

an induction venturi including a combustion air inlet connected and in communication with said combustion air supply, an exhaust gas inlet connected and in communication with said exhaust manifold, an outlet, a venturi section terminating at a venturi throat exit end and in communication with said combustion air inlet, an expansion section positioned between and in communication with said venturi section exit end and said outlet, and at least one induction port terminating separate from and adjacent said venturi throat exit end within said expansion section.

2. The internal combustion engine of claim 1, further comprising a housing with an inner chamber, said venturi section positioned within said inner chamber.

3. The internal combustion engine of claim 2, wherein said venturi section has a generally cone shape, said inner chamber surrounding said venturi section and being in communication with said expansion section.

4. The internal combustion engine of claim 3, wherein said venturi section terminates at an exit end adjacent said venturi throat, each of said exit end and said expansion section having a generally circular cross section, said at least one induction port comprising an annular space between said exit end and said expansion section.

5. The internal combustion engine of claim 4, wherein said at least one induction port comprises an annular space which is positioned radially around said exit end.

6. The internal combustion engine of claim 4, wherein said venturi section has an outer surface extending from said exit end which is disposed at an angle of approximately 30°

relative to a longitudinal axis of said venturi section.

7. The internal combustion engine of claim 4, further comprising a liner disposed within said housing and defining said expansion section.

8. The internal combustion engine of claim 2, wherein said venturi section is separate from and carried by said housing.

9. The internal combustion engine of claim 1, wherein said combustion air supply includes an air-to-air aftercooler.

10. An induction venturi for inducing exhaust gas into a flow of combustion air in an exhaust gas recirculation system of an internal combustion engine, the internal combustion engine including a combustion air supply and an exhaust manifold, said induction venturi comprising:

a housing having a combustion air inlet for receiving combustion air from the combustion air supply, an exhaust gas inlet for receiving exhaust gas from the exhaust manifold, an outlet, and an inner chamber in communication with each of said combustion air inlet, said exhaust gas inlet and said outlet;

a venturi section terminating at a venturi throat exit end and in communication with said combustion air inlet, said venturi section positioned within said inner chamber;

an expansion section positioned between and in communication with said venturi section exit end and said outlet; and

at least one induction port defined by at least one of said housing and said venturi section, said at least one induction port terminating separate from and adjacent said venturi throat exit end within said expansion section radially outwardly of said venturi throat.

11. The induction venturi of claim 10, wherein said at least one induction port comprises a single induction port which is defined by each of said housing and said venturi throat.

12. The induction venturi of claim 10, wherein said venturi section has a generally cone shape, said inner chamber surrounding said venturi section and being in communication with said expansion section.

13. The induction venturi of claim 12, wherein said venturi section terminates at an exit end adjacent said venturi throat, each of said exit end and said expansion section having a generally circular cross section, said at least one induction port comprising an annular space between said exit end and said expansion section.

14. The induction venturi of claim 13, wherein said at least one induction port comprises an annular space which is positioned radially around said exit end.

15. The induction venturi of claim 13, wherein said venturi section has an outer surface extending from said exit end which is disposed at an angle of approximately 30°

relative to a longitudinal axis of said venturi section.

16. The induction venturi of claim 13, further comprising a liner disposed within said housing and defining said expansion section.

17. The induction venturi of claim 12, wherein said venturi section is separate from and carried by said housing.

18. The induction venturi of claim 10, wherein said combustion air supply includes an air-to-air aftercooler.

19. A method of operating an internal combustion engine having an exhaust gas recirculation system, comprising the steps of:

providing a combustion air supply;

providing an exhaust manifold;

providing an induction venturi including a combustion air inlet connected and in communication with said combustion air supply, an exhaust gas inlet connected and in communication with said exhaust manifold, an outlet, a venturi section terminating at a venturi throat and in communication with said combustion air inlet, an expansion section positioned between and in communication with said venturi section and said outlet, and at least one induction port terminating adjacent said venturi throat and within said expansion section;

transporting combustion air from said combustion air supply, through said combustion air inlet and through said venturi section into said expansion section; and

transporting exhaust gas from said exhaust gas manifold, through said at least one induction port and into said expansion section separately from the combustion air.

20. The method of claim 19, wherein said induction venturi includes a housing with an inner chamber, and said venturi section is positioned within said housing and has a generally cone shape, said inner chamber surrounding said venturi section and being in communication with said expansion section.

21. The method of claim 20, wherein said venturi section terminates at an exit end adjacent said venturi throat, each of said exit end and said expansion section having a generally circular cross section, said at least one induction port comprising an annular space between said exit end and said expansion section.

22. The method of claim 21, wherein said at least one induction port comprises an annular space which is positioned radially around said exit end.

23. The induction venturi of claim 21, wherein said venturi section has an outer surface extending from said exit end which is disposed at an angle of approximately 30°

relative to a longitudinal axis of said venturi section.