Two-cycle carburetor gasoline engine for snowmobiles, lawn mowers, motorcycles or outboard motors

• US 6,216,447 B1
• Filed: 08/06/1999
• Issued: 04/17/2001
• Est. Priority Date: 02/10/1997
• Status: Expired due to Term

• Current Assignee: Mats Tikka
• Original Assignee: Mats Tikka
• Inventors: Tikka, Mats
• Primary Examiner(s): Denion, Thomas
• Assistant Examiner(s): TRIEU, THAI BA
• Application Number:
  US09/369,633
• Time in Patent Office: 620 Days
• Field of Search: 602/72, 602/99, 602/98, 603/07, 603/20
• US Class Current: 60/272
• CPC Class Codes: B01D 53/8696 Controlling the catalytic process
• CPC Class Codes: B01D 53/9454 characterised by a specific device
• CPC Class Codes: B01D 53/9495 Controlling the catalytic process
• CPC Class Codes: F01N 13/02 having two or more separate silencers in series
• CPC Class Codes: F01N 2240/02 a heat exchanger
• CPC Class Codes: F01N 2250/04 afterburning and catalytic conversion
• CPC Class Codes: F01N 3/18 characterised by methods of operation; Control
• CPC Class Codes: F01N 3/20 specially adapted for catalytic conversion F01N3/22 takes precedence; Methods of operation or control of catalytic converters
• CPC Class Codes: F01N 3/26 Construction of thermal reactors
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A two cycle engine comprising an induction system to induct fuel and air into said two cycle engine, at least one cylinder arrangement to combust the fuel and air mixture of said two cycle engine, and a piston arrangement disposed in said at least one cylinder arrangement. The at least one cylinder arrangement is configured to combust the fuel and air mixture of the two cycle engine during each two cycle movement of said piston arrangement. The engine also has an ignition system disposed to combust the fuel and air mixture in the at least one cylinder during each two cycle movement of the piston arrangement and an exhaust system to exhaust gases from the at least one cylinder. The exhaust system comprises a reactor and a precombustion chamber, the precombustion chamber is disposed between the at least one cylinder and the reactor. The engine also includes a heat exchanger configured and disposed to transfer heat from exhaust gases from the reactor to the precombustion chamber.

Claims

1. A two cycle carbureted gasoline engine comprising:

an induction system to induct fuel and air into said two cycle engine;

at least one cylinder arrangement to combust the fuel and air mixture of said two cycle engine;

a piston arrangement disposed in said at least one cylinder arrangement;

said at least one cylinder arrangement being configured to combust the fuel and air mixture of said two cycle engine during each two cycle movement of said piston arrangement;

an ignition system disposed to combust the fuel and air mixture in said at least one cylinder during each two cycle movement of said piston arrangement;

an exhaust system to exhaust gases from said at least one cylinder, said exhaust system comprising;

reactor and a precombustion chamber;

said precombustion chamber being disposed between said at least one cylinder and said reactor; and

a heat exchanger configured and disposed to transfer heat from exhaust gases from said reactor to said precombustion chamber.

2. The two cycle carbureted gasoline engine according to claim 1 in combination with one of:

a snowmobile;

an outboard motor;

a motorcycle; and

a lawn tractor.

3. The two cycle carbureted gasoline engine according to claim 2, wherein said precombustion chamber comprises an expansion chamber for tuning the resistance of engine exhaust gases.

4. The two cycle carbureted gasoline engine according to claim 3, comprising a second heat exchanger downstream in the reactor exhaust gases to transfer heat to the gas present in a conduit extending between said precombustion chamber and a reactor inlet.

5. The two cycle carbureted gasoline engine according to claim 4, wherein said heat exchanger comprises a conduit arrangement that extends transversely through said expansion chamber, said conduit arrangement having an aerodynamic cross-sectional shape so as to minimize any disturbing effect on the flow in the expansion chamber.

6. The two cycle carbureted gasoline engine according to claim 5, wherein said heat exchanger conduit arrangement has a cross-sectional shape essentially in the form of a symmetrical wing-profile, and is provided with fins.

7. The two cycle carbureted gasoline engine according to claim 2, wherein said reactor comprises a catalytic reactor and said precombustion chamber comprises an expansion chamber for tuning the resistance of engine exhaust gases.

8. The two cycle carbureted gasoline engine according to claim 7, comprising a second heat exchanger downstream in the reactor exhaust gases to transfer heat to the gas present in a conduit extending between said precombustion chamber and a reactor inlet.

9. The two cycle carbureted gasoline engine according to claim 8, wherein said heat exchanger comprises a conduit arrangement that extends transversely through said expansion chamber, said conduit arrangement having an aerodynamic cross-sectional shape so as to minimize any disturbing effect on the flow in the expansion chamber.

10. The two cycle carbureted gasoline engine according to claim 9, wherein said heat exchanger conduit arrangement has a cross-sectional shape essentially in the form of a symmetrical wing-profile, and is provided with fins.

11. A method of operating a two cycle engine, the two cycle engine comprising:

an induction system to induct fuel and air into the two cycle engine, at least one cylinder arrangement to combust the fuel and air mixture of the two cycle engine, a piston arrangement disposed in the at least one cylinder arrangement, the at least one cylinder arrangement being configured to combust the fuel and air mixture of the two cycle engine during each two cycle movement of the piston arrangement, an ignition system disposed to combust the fuel and air mixture in the at least one cylinder during each two cycle movement of the piston arrangement, an exhaust system to exhaust gases from the at least one cylinder, the exhaust system comprising;

a reactor and a precombustion chamber, the precombustion chamber being disposed between the at least one cylinder and the reactor, and a heat exchanger configured and disposed to transfer heat from exhaust gases from the reactor to the precombustion chamber, said method comprising the steps of;

providing fuel and air to the engine to be combusted in the engine;

combusting fuel and air in the cylinder to drive the piston arrangement;

exhausting exhaust gases from the reactor;

transferring heat in the heat exchanger from exhaust gases from the reactor to the precombustion chamber.

12. The method according to claim 11 comprising the step of initiating a precombustion upstream of the actual reactor combustion, with the aid of heat taken from the reactor exhaust gases.

13. The method according to claim 12, wherein the precombustion chamber comprises an expansion chamber, said method comprises the steps of:

initiating the precombustion process in the engine exhaust-gas expansion chamber; and

using the expansion chamber to tune the exhaust resistance of the engine.

14. A gasoline engine comprising:

an induction system to induct fuel and air into said engine;

at least one cylinder arrangement to combust the fuel and air mixture of said engine;

a piston arrangement disposed in said at least one cylinder arrangement;

said at least one cylinder arrangement being configured to combust the fuel and air mixture of said engine during each movement of said piston arrangement;

an ignition system disposed to combust the fuel and air mixture in said at least one cylinder during each movement of said piston arrangement;

an exhaust system to exhaust gases from said at least one cylinder, said exhaust system comprising;

a reactor and a precombustion chamber;

said precombustion chamber being disposed between said at least one cylinder and said reactor; and

a heat exchanger configured and disposed to transfer heat from exhaust gases from said reactor to said precombustion chamber.

15. The gasoline engine according to claim 14 in combination with one of:

a snowmobile;

an outboard motor;

a motorcycle; and

a lawn tractor.

16. The gasoline engine according to claim 15, wherein said precombustion chamber comprises an expansion chamber for tuning the resistance of engine exhaust gases.

17. The gasoline engine according to claim 16, comprising a second heat exchanger downstream in the reactor exhaust gases to transfer heat to the gas present in a conduit extending between said precombustion chamber and a reactor inlet.

18. The gasoline engine according to claim 17, wherein said heat exchanger comprises a conduit arrangement that extends transversely through said expansion chamber, said conduit arrangement having an aerodynamic cross-sectional shape so as to minimize any disturbing effect on the flow in the expansion chamber, and said heat exchanger conduit arrangement has a cross-sectional shape essentially in the form of a symmetrical wing-profile, and is provided with fins.

19. The gasoline engine according to claim 15, wherein said reactor comprises a catalytic reactor and said precombustion chamber comprises an expansion chamber for tuning the resistance of engine exhaust gases.

20. The gasoline engine according to claim 19, comprising a second heat exchanger downstream in the reactor exhaust gases to transfer heat to the gas present in a conduit extending between said precombustion chamber and a reactor inlet, said heat exchanger comprises a conduit arrangement that extends transversely through said expansion chamber, said conduit arrangement having an aerodynamic cross-sectional shape so as to minimize any disturbing effect on the flow in the expansion chamber, and said heat exchanger conduit arrangement has a cross-sectional shape essentially in the form of a symmetrical wing-profile, and is provided with fins.