In an apparatus for controlling an air/fuel ratio of a general-purpose internal combustion engine using mixed fuel containing alcohol and gasoline and operated at a desired engine speed inputted by the operator while a throttle opening is regulated such that a detected engine speed converges to the inputted desired engine speed, a fuel injection amount for mixed fuel determined based on fuel injection amount characteristics is increased/decreased when a load is kept constant and the output air/fuel ratio (at which an output of the engine becomes maximum) is estimated. And the fuel injection amount is corrected based on the estimated air/fuel ratio, thereby enabling to estimate the output air/fuel ratio without using an expensive air/fuel ratio sensor and to feedback-control the fuel injection amount such that the engine is operated at the output air/fuel ratio.

A mechanical fuel lockout switch for a dual fuel engine includes a mechanical fuel valve actuatable between a first position and a second position to selectively control fuel flow to the dual fuel engine from a first fuel source through a first fuel line and a second fuel source through a second fuel line. The mechanical fuel lockout switch may also include a fuel lockout apparatus coupled to the mechanical fuel valve. The mechanical fuel valve may be configured to allow communication between the first fuel source and the dual fuel engine and prevent communication between the second fuel source and the dual fuel engine while in the first position, and prevent communication between the first fuel source and the dual fuel engine while in the second position.

A fuel selector for use with a dual fuel generator includes a selector plate, a first fuel valve assembly positioned adjacent the selector plate and actuatable between an ON position and an OFF position to selectively control a first fuel flow to an engine of the dual fuel generator, and a second fuel valve assembly positioned adjacent the selector plate and actuatable between an ON position and an OFF position to selectively control a second fuel flow to the engine of the dual fuel generator. A selector switch coupled to the selector plate is linearly translatable from a first position to a second position, so as to enable positioning of only one of the first fuel valve assembly and the second fuel valve assembly in the ON position at a given time, such that the first and second fuel valve assemblies cannot be in the ON position concurrently.

A fuel selector for use with a dual fuel generator includes a selector plate, a first fuel valve assembly positioned adjacent the selector plate and actuatable between an ON position and an OFF position to selectively control a first fuel flow to an engine of the dual fuel generator, and a second fuel valve assembly positioned adjacent the selector plate and actuatable between an ON position and an OFF position to selectively control a second fuel flow to the engine of the dual fuel generator. A selector switch coupled to the selector plate is linearly translatable from a first position to a second position, so as to enable positioning of only one of the first fuel valve assembly and the second fuel valve assembly in the ON position at a given time, such that the first and second fuel valve assemblies cannot be in the ON position concurrently.

An engine system operating and control strategy includes autoigniting a directly injected pilot fuel to ignite a primary fuel in a cylinder in a first engine cycle. The strategy further includes comparing data indicative of a heat release in a cylinder in the first engine cycle to phasing error criteria for an earlier pilot shot of the pilot fuel and a later shot of the pilot fuel. A quantity of one or more pilot shots in a subsequent engine cycle is varied, based on the comparison. Pilot shot quantity can be varied closed loop to obtain desired combustion phasing characteristics, such as when a characteristic of a primary fuel is changed during operation. Related apparatus and control logic is also disclosed.

An internal combustion engine system is described herein. The system uses a mixer to mix two fuels to provide for a transition from using only one of the fuels to using only the other fuel as power demand changes. The output of the mixer is provided to the engine as a primary fuel. A controller opens and closes throttle valves to adjust the relative concentrations of a first fuel (e.g., diesel) and a second fuel (e.g., methanol) that enter the mixer. In some examples, rather than removing the desired performance and/or environmental benefits achieved by using the second fuel at power demand levels greater than the maximum achievable by only using the second fuel, the systems described herein allow the use of at least a portion of the second fuel in the primary fuel at those power demand levels.

An engine system operating and control strategy includes autoigniting a directly injected pilot fuel to ignite a primary fuel in a cylinder in a first engine cycle. The strategy further includes comparing data indicative of a heat release in a cylinder in the first engine cycle to phasing error criteria for an earlier pilot shot of the pilot fuel and a later shot of the pilot fuel. A quantity of one or more pilot shots in a subsequent engine cycle is varied, based on the comparison. Pilot shot quantity can be varied closed loop to obtain desired combustion phasing characteristics, such as when a characteristic of a primary fuel is changed during operation. Related apparatus and control logic is also disclosed.

The present disclosure provides a multifunctional switch base assembly and a control method thereof, solving problems such as safety of switching between fuel and gas. The multifunctional switch base assembly comprises a switch base, where a switch knob as well as a gas switch assembly and an oil line switch assembly which are controlled by the switch knob to turn on or off are mounted on the switch base, the gas switch assembly and the oil line switch assembly are connected to a control module, and the control module is connected to a storage battery and an ignition coil. The present disclosure has the advantages of high safety, stable switching and the like.