Batteryless dual fuel engine with liquid fuel cut-off

Patent metadata

Field	Value
Publication number	US-10697398-B2
Application number	US-201514925441-A
Country	US
Kind code	B2
Filing date	Oct 28, 2015
Priority date	Jun 12, 2015
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

A dual fuel engine includes an engine operable on a gaseous fuel and a liquid fuel and a switch to change operation of the engine between gaseous fuel and liquid fuel. The dual fuel engine also includes a carburetor attached to an intake of the engine to mix air and fuel and connect to a gaseous fuel source and a liquid fuel source. A liquid fuel cut-off attaches to the carburetor to interrupt liquid fuel upon actuation of the switch from liquid fuel to gaseous fuel.

First claim

What is claimed is:

1. A dual fuel engine comprising:
an engine operable on a gaseous fuel and a liquid fuel;
a switch to change operation of the engine between gaseous fuel and liquid fuel;
a carburetor attached to an intake of the engine to mix air and fuel and connect to a gaseous fuel source and a liquid fuel source;
a liquid fuel valve positioned along a liquid fuel line coupling the liquid fuel source to the carburetor;
a gaseous fuel valve positioned along a gaseous fuel line coupling the gaseous fuel source to the carburetor; and
a liquid fuel cut-off incorporated into the carburetor to interrupt liquid fuel upon actuation of the switch from liquid fuel to gaseous fuel.

2. The dual fuel engine of claim 1 , wherein the engine is a pull start, batteryless engine.

3. The dual fuel engine of claim 1 , wherein the gaseous fuel is LPG and the liquid fuel is gasoline.

4. The dual fuel engine of claim 1 , wherein the engine is a pull-start engine having an electrical power generator to supply electrical power.

5. The dual fuel engine of claim 4 , wherein the switch is an electro-mechanical switch connecting one fuel source to the carburetor and connected to the electrical power generator; and
wherein the liquid fuel cut-off is a solenoid connected to open and close a fuel path to the pull-start engine in response to reception of electrical power from the switch.

6. The dual fuel engine of claim 4 , wherein the liquid fuel cut-off is a solenoid valve that operates within the carburetor to control liquid fuel flow to the engine and is powered by the electrical power generator.

7. The dual fuel engine of claim 6 , wherein the switch selectively powers the solenoid valve by controlling electrical connection between the solenoid valve and the electrical power generator.

8. The dual fuel engine of claim 6 , wherein the solenoid valve is normally open to provide liquid fuel to the engine when the solenoid valve is unpowered.

9. The dual fuel engine of claim 8 , wherein a pull-starter drives the electrical power generator to power and close the solenoid valve while starting the engine on gaseous fuel.

10. The dual fuel engine of claim 6 , wherein the electrical power generator comprises a magneto or an alternator coupled to a voltage regulator to provide a regulated voltage to the solenoid valve.

11. The dual fuel engine of claim 6 , wherein the solenoid valve is open to provide liquid fuel to the engine when the solenoid valve is powered.

12. The dual fuel engine of claim 11 , wherein a pull-starter drives the electrical power generator to power and open the solenoid valve while starting the engine on liquid fuel.

13. The dual fuel engine of claim 6 further comprising a microcontroller to close the solenoid valve when the engine operates on gaseous fuel and open the solenoid valve to operate the engine on liquid fuel.

14. The dual fuel engine of claim 13 , wherein the microcontroller closes the solenoid valve during engine shutdown from operation on liquid fuel.

15. The dual fuel engine of claim 1 , wherein the liquid fuel cut-off is manually actuated to interrupt liquid fuel.

16. The dual fuel engine of claim 1 , wherein the liquid fuel cut-off actuates to interrupt liquid fuel free from linear motion.

17. The dual fuel engine of claim 1 , wherein the liquid fuel cut-off comprises:
a rotating shaft extending through an aperture in the carburetor;
a fuel seal around the shaft to seal the aperture; and
a blocking member coupled to the shaft in the carburetor that rotates between a blocking and a non-blocking position to selectively block a liquid fuel path to the engine.

18. The dual fuel engine of claim 17 further comprising:
a lever coupled to the shaft outside the carburetor;
a spring coupled to the lever to hold the blocking member in either the blocking or non-blocking position; and
a cable coupled to the lever to pull against the spring and rotate the blocking member to the other of the blocking or non-blocking positions.

19. The dual fuel engine of claim 1 , wherein the liquid fuel cut-off is magnetically actuated to selectively interrupt liquid fuel.

20. The dual fuel engine of claim 1 further comprising:
a spring pushing the liquid fuel cut-off to interrupt liquid fuel; and
an actuating magnet coupled to the carburetor to selectively pull the liquid fuel cut-off against the spring away from a position interrupting liquid fuel.

21. The dual fuel engine of claim 20 further comprising a housing at least partially enclosing the liquid fuel cutoff, the housing including:
a first section enclosing a plunger of the liquid fuel cut-off to the carburetor and holding the spring against the plunger; and
a second section coupled to the first section and enclosing the actuating magnet.

22. The dual fuel engine of claim 1 , wherein the liquid fuel cut-off is physically attached to an outer surface of the carburetor.

23. A batteryless dual fuel generator comprising:
a housing containing a pull start engine coupled to drive an alternator, the engine operable on a gaseous fuel and a liquid fuel;
a carburetor attached to an intake of the engine comprising:
a throat to mix fuel with air,
a float bowl, and
a fuel passage extending from the float bowl to the throat to provide liquid fuel; and

a fuel shutoff attached to the carburetor to close the fuel passage upon selection of engine operation to gaseous fuel.

24. The batteryless dual fuel generator of claim 23 , wherein the fuel shutoff actuates to close the fuel passage free from linear motion.

25. The batteryless dual fuel generator of claim 23 , wherein the fuel shutoff comprises:
a rotating shaft extending through an opening in the carburetor; and
a valve member coupled to the shaft in the carburetor that rotates to control fuel flow into the fuel passage.

26. The batteryless dual fuel generator of claim 25 , wherein the valve member is positioned in the float bowl and the shaft extends substantially horizontal through the opening.

27. The batteryless dual fuel generator of claim 25 , wherein the valve member has a flow passage that aligns with the fuel passage to control fuel flow into the fuel passage.

28. The batteryless dual fuel generator of claim 25 further comprising:
a compression spring on the shaft in the carburetor pushing the valve member to close the fuel passage; and
a plug in the opening surrounding the shaft to hold the compression spring against the valve member.

29. The batteryless dual fuel generator of claim 28 further comprising:
a lever coupled to the shaft outside the carburetor; and
a cable coupled to the lever to actuate the valve member to open and close the fuel passage.

30. The batteryless dual fuel generator of claim 28 further comprising one or more fuel seals within the plug to seal around the shaft.

31. The batteryless dual fuel generator of claim 23 , wherein the fuel shutoff is magnetically actuated to selectively close the fuel passage, controlled by a manually actuated magnet coupled to the carburetor.

32. The batteryless dual fuel generator of claim 23 further comprising:
a spring pushing the fuel shutoff to close the fuel passage; and
an actuating magnet coupled to the carburetor to selectively pull the fuel shutoff against the spring to open the

Assignees

• Champion Engine Tech Llc
• Champion Power Equipment Inc

Inventors

• Collie Kendall J
• Sarder Mark J
• Sotiriades Aleko D
• Dehn James J
• Jenison Leigh
• Sato Hiroaki

Classifications

• Y02T10/30

  Use of alternative fuels, e.g. biofuels · CPC title

• F02M13/08 Primary

  Carburettors adapted to use liquid and gaseous fuels, e.g. alternatively · CPC title

• F02M17/10

  Carburettors having one or more fuel passages opening in valve-member of air throttle · CPC title

• F02D19/0613

  Switch-over from one fuel to another (F02D19/081 takes precedence) · CPC title

• F02D41/062

  for starting (F02D41/061 takes precedence) · CPC title