GASEOUS FUEL MIXING DEVICE

• US 20080290531A1
• Filed: 05/12/2008
• Published: 11/27/2008
• Est. Priority Date: 05/25/2007
• Status: Active Grant

• Current Assignee: Briggs & Stratton LLC (Briggs & Stratton Corporation)
• Original Assignee: Briggs & Stratton Corporation
• Inventors: Meronek, Jimmy L., Nickels, Travis J.
• Granted Patent: US 7,905,469 B2
• Time in Patent Office: Days
• US Class Current: 261/52
• CPC Class Codes: F02M 13/08 Carburettors adapted to use liquid and gaseous fuels, e.g. alternatively
• CPC Class Codes: F02M 21/0239 Pressure or flow regulators therefor
• CPC Class Codes: F02M 21/047 Venturi mixer
• CPC Class Codes: Y02T 10/30 Use of alternative fuels, e.g. biofuels
• CPC Class Codes: Y10S 261/74 Valve actuation; electrical

Abstract

A gaseous fuel mixing device includes a body having an air/fuel passageway and a gaseous fuel passageway in fluid communication with the air/fuel passageway, a throttle valve pivotably coupled to the body and positioned in the air/fuel passageway, and an intake unit coupled to the body. The intake unit includes an inlet configured to be fluidly connected with a source of gaseous fuel, a first jet fluidly communicating the inlet and the gaseous fuel passageway, a second jet selectively fluidly communicating the inlet and the gaseous fuel passageway, and a selector valve operable to control a flow of gaseous fuel through the second jet.

Claims

1. A gaseous fuel mixing device configured for use with an internal combustion engine, the mixing device comprising:

a body including an air/fuel passageway, and a gaseous fuel passageway in fluid communication with the air/fuel passageway;

a throttle valve pivotably coupled to the body and positioned in the air/fuel passageway;

an intake unit coupled to the body, the intake unit including

an inlet configured to be fluidly connected with a source of gaseous fuel;

a first jet fluidly communicating the inlet and the gaseous fuel passageway;

a second jet selectively fluidly communicating the inlet and the gaseous fuel passageway; and

a selector valve operable to control a flow of gaseous fuel through the second jet.

2. The gaseous fuel mixing device of claim 1, wherein the intake unit includes a gaseous fuel chamber in fluid communication with the gaseous fuel passageway, wherein the first jet is configured to transfer gaseous fuel from the inlet to the gaseous fuel chamber, and wherein the second jet is configured to transfer gaseous fuel, upon actuation of the selector valve, from the inlet to the gaseous fuel chamber.

3. The gaseous fuel mixing device of claim 2, further comprising an idle jet housing at least partially positioned within the gaseous fuel chamber, wherein the idle jet housing includes a second gaseous fuel chamber in fluid communication with the gaseous fuel passageway, and at least one orifice selectively fluidly communicating the first gaseous fuel chamber in the intake unit with the second gaseous fuel chamber.

4. The gaseous fuel mixing device of claim 3, wherein the selector valve is configured to control the flow of gaseous fuel through the second jet and the orifice in the idle jet housing.

5. The gaseous fuel mixing device of claim 3, wherein the body includes a second gaseous fuel passageway in fluid communication with the air/fuel passageway, and wherein the second gaseous fuel passageway directly fluidly connects the first gaseous fuel chamber in the intake unit with the air/fuel passageway.

6. The gaseous fuel mixing device of claim 5, wherein the second gaseous fuel passageway is configured to receive gaseous fuel from at least one of the first and second jets when the throttle valve is substantially open.

7. The gaseous fuel mixing device of claim 5, wherein the first gaseous fuel passageway is configured to receive gaseous fuel from at least one of the first and second jets, via the orifice in the idle jet housing, when the throttle valve is substantially closed.

8. The gaseous fuel mixing device of claim 3, wherein the orifice has a cross-sectional area less than a cross-sectional area of the first jet, and wherein the cross-sectional area of the orifice is less than a cross-sectional area of the second jet.

9. The gaseous fuel mixing device of claim 1, wherein the selector valve is configured to be moved between a first position, in which the second jet is at least partially closed, and a second position, in which the second jet is substantially open.

10. The gaseous fuel mixing device of claim 1, wherein the body includes a second air/fuel passageway and a second gaseous fuel passageway in fluid communication with the second air/fuel passageway, and wherein each of the first and second gaseous fuel passageways is configured to draw an amount of gaseous fuel, based upon individual demand of fuel through the respective first and second air/fuel passageways, from the intake unit.

11. The gaseous fuel mixing device of claim 1, wherein the body includes a modified carburetor body originally configured for use with a liquid fuel, wherein the gaseous fuel passageway has an inlet in communication with an exterior of the body and an outlet in communication with the air/fuel passageway, and wherein the body includes a closed liquid fuel passageway.

12. A gaseous fuel mixing device configured for use with an internal combustion engine, the mixing device comprising:

a body including

a first air/fuel passageway;

a second air/fuel passageway;

a first gaseous fuel passageway in fluid communication with the first air/fuel passageway;

a second gaseous fuel passageway in fluid communication with the second air/fuel passageway;

a first throttle valve pivotably coupled to the body and positioned in the first air/fuel passageway;

a second throttle valve pivotably coupled to the body and positioned in the second air/fuel passageway; and

an intake unit coupled to the body and in fluid communication with a source of gaseous fuel, wherein each of the first and second gaseous fuel passageways is configured to draw an amount of gaseous fuel, based upon individual demand of fuel through the respective first and second air/fuel passageways, from the intake unit.

13. The gaseous fuel mixing device of claim 12, wherein the intake unit includes

an inlet configured to be fluidly connected with the source of gaseous fuel;

a first jet fluidly communicating the inlet with the first and second gaseous fuel passageways;

a second jet selectively fluidly communicating the inlet with the first and second gaseous fuel passageways; and

a selector valve configured to control a flow of gaseous fuel through the second jet.

14. The gaseous fuel mixing device of claim 13, wherein the intake unit includes a gaseous fuel chamber in fluid communication with the first and second gaseous fuel passageways, wherein the first jet is configured to transfer gaseous fuel from the inlet to the gaseous fuel chamber, and wherein the second jet is configured to transfer gaseous fuel, upon actuation of the selector valve, from the inlet to the gaseous fuel chamber.

15. The gaseous fuel mixing device of claim 14, further comprising an idle jet housing at least partially positioned within the gaseous fuel chamber, wherein the idle jet housing includes a second gaseous fuel chamber in fluid communication with the first and second gaseous fuel passageways, and at least one orifice selectively fluidly communicating the first gaseous fuel chamber in the intake unit with the second gaseous fuel chamber.

16. The gaseous fuel mixing device of claim 15, wherein the selector valve is configured to control the flow of gaseous fuel through the second jet and the orifice in the idle jet housing.

17. The gaseous fuel mixing device of claim 15, wherein the body includes

a third gaseous fuel passageway in fluid communication with the first air/fuel passageway;

and

a fourth gaseous fuel passageway in fluid communication with the second air/fuel passageway, wherein the third gaseous fuel passageway directly fluidly connects the first gaseous fuel chamber in the intake unit with the first air/fuel passageway, and wherein the fourth gaseous fuel passageway directly fluidly connects the first gaseous fuel chamber in the intake unit with the second air/fuel passageway.

18. The gaseous fuel mixing device of claim 17, wherein the third and fourth gaseous fuel passageways are each configured to draw gaseous fuel from at least one of the first and second jets when the throttle valve is substantially open.

19. The gaseous fuel mixing device of claim 17, wherein the first and second gaseous fuel passageways are each configured to draw gaseous fuel from at least one of the first and second jets, via the orifice in the idle jet housing, when the throttle valve is substantially closed.

20. The gaseous fuel mixing device of claim 15, wherein the orifice has a cross-sectional area less than a cross-sectional area of the first jet, and wherein the cross-sectional area of the orifice is less than a cross-sectional area of the second jet.

21. The gaseous fuel mixing device of claim 13, wherein the selector valve is configured to be moved between a first position, in which the second jet is at least partially closed, and a second position, in which the second jet is substantially open.

22. The gaseous fuel mixing device of claim 12, wherein the body includes a modified carburetor body originally configured for use with a liquid fuel, wherein each of the first and second gaseous fuel passageways has an inlet in communication with an exterior of the body, and wherein the body includes a closed liquid fuel passageway.

23. A gaseous fuel mixing device configured for use with an internal combustion engine, the mixing device comprising:

a modified carburetor body, originally configured for use with a liquid fuel, including

an air/fuel passageway;

a gaseous fuel passageway having an inlet in communication with an exterior of the body and an outlet in communication with the air/fuel passageway;

a closed liquid fuel passageway;

a throttle valve pivotably coupled to the carburetor body and positioned in the air/fuel passageway; and

an intake unit coupled to the carburetor body, the intake unit configured to deliver gaseous fuel to the gaseous fuel passageway in the carburetor body.

24. The gaseous fuel mixing device of claim 23, wherein the intake unit includes

an inlet configured to be fluidly connected with a source of gaseous fuel;

a first jet fluidly communicating the inlet with the gaseous fuel passageway;

a second jet selectively fluidly communicating the inlet with the gaseous fuel passageway; and

a selector valve operable to control a flow of gaseous fuel through the second jet.

25. The gaseous fuel mixing device of claim 24, wherein the intake unit includes a gaseous fuel chamber in fluid communication with the gaseous fuel passageway, wherein the first jet is configured to transfer gaseous fuel from the inlet to the gaseous fuel chamber, and wherein the second jet is configured to transfer gaseous fuel, upon actuation of the selector valve, from the inlet to the gaseous fuel chamber.

26. The gaseous fuel mixing device of claim 25, further comprising an idle jet housing at least partially positioned within the gaseous fuel chamber, wherein the idle jet housing includes a second gaseous fuel chamber in fluid communication with the gaseous fuel passageway, and at least one orifice selectively fluidly communicating the first gaseous fuel chamber in the intake unit with the second gaseous fuel chamber.

27. The gaseous fuel mixing device of claim 26, wherein the selector valve is configured to control the flow of gaseous fuel through the second jet and the orifice in the idle jet housing.

28. The gaseous fuel mixing device of claim 25, wherein the body includes a second gaseous fuel passageway in fluid communication with the air/fuel passageway, and wherein the second gaseous fuel passageway directly fluidly connects the first gaseous fuel chamber in the intake unit with the air/fuel passageway.

29. The gaseous fuel mixing device of claim 28, wherein the second gaseous fuel passageway is configured to draw gaseous fuel from at least one of the first and second jets when the throttle valve is substantially open.

30. The gaseous fuel mixing device of claim 28, wherein the first gaseous fuel passageway is configured to draw gaseous fuel from at least one of the first and second jets, via the orifice in the idle jet housing, when the throttle valve is substantially closed.

31. The gaseous fuel mixing device of claim 26, wherein the orifice has a cross-sectional area less than a cross-sectional area of the first jet, and wherein the cross-sectional area of the orifice is less than a cross-sectional area of the second jet.

32. The gaseous fuel mixing device of claim 23, wherein the selector valve is configured to be moved between a first position, in which the second jet is at least partially closed, and a second position, in which the second jet is substantially open.

33. The gaseous fuel mixing device of claim 23, wherein the body includes a second air/fuel passageway and a second gaseous fuel passageway in fluid communication with the second air/fuel passageway, and wherein each of the first and second gaseous fuel passageways is configured to draw an amount of gaseous fuel, based upon individual demand of fuel through the respective first and second air/fuel passageways, from the intake unit.

34. A method of converting a carburetor from operating using a liquid fuel to operating using a gaseous fuel, the method comprising:

providing a carburetor body including an air/fuel passageway;

creating a gaseous fuel passageway through a portion of the body to fluidly communicate the gaseous fuel passageway with the air/fuel passageway; and

closing a liquid fuel passageway in the body.

35. The method of claim 34, wherein closing the liquid fuel passageway includes closing an end of the liquid fuel passageway exposed to an exterior of the carburetor body.

36. The method of claim 34, wherein creating a gaseous fuel passageway includes boring the gaseous fuel passageway through the body.

37. The method of claim 34, wherein closing the liquid fuel passageway includes plugging the liquid fuel passageway with an adhesive.

38. The method of claim 34, further comprising:

coupling an intake unit to the carburetor body, the intake unit configured to fluidly communicate with a source of gaseous fuel; and

positioning an orifice between an inlet in the intake unit and the gaseous fuel passageway to meter a flow of gaseous fuel through the gaseous fuel passageway.

39. The method of claim 38, further comprising:

positioning an idle jet housing between the carburetor body and the intake unit;

fluidly communicating a chamber in the idle jet housing with the gaseous fuel passageway; and

positioning a second orifice in the idle jet housing to meter the flow of gaseous fuel entering the chamber in the idle jet housing and through the gaseous fuel passageway.

40. The method of claim 38, further comprising coupling a selector valve to the intake unit to control the flow of gaseous fuel through the orifice.