In at least some implementations, a charge forming device includes a body that has a throttle bore, a throttle valve associated with the throttle bore, a coupler and an actuator. The throttle has a valve head received within and movable relative to the throttle bore, and a valve shaft to which the valve head is coupled. The coupler is connected to the valve shaft and carries or includes a sensor element. And the actuator has a drive shaft coupled to the coupler so that rotation of the drive shaft is transmitted to the coupler and the valve shaft.

Present embodiments provide a throttle body which may be used with a variety of engines of different manufacturers. The throttle body may be used to replace mechanical or hydraulically controlled carburetors with electronic fuel injection. The throttle body may provide improved fuel pathways and fuel injector placement.

In at least some implementations, a charge forming device includes a body that has a throttle bore, a throttle valve associated with the throttle bore, a coupler and an actuator. The throttle has a valve head received within and movable relative to the throttle bore, and a valve shaft to which the valve head is coupled. The coupler is connected to the valve shaft and carries or includes a sensor element. And the actuator has a drive shaft coupled to the coupler so that rotation of the drive shaft is transmitted to the coupler and the valve shaft.

A port fuel injection system includes a fuel pump configured to produce a flow of pressurized liquid fuel at a pressure between 10 and 50 bar. A fuel rail is connected to receive the flow of pressurized liquid fuel from the fuel pump, the fuel rail. A plurality of fuel injectors, including one fuel injector positioned in the intake port of each engine cylinder upstream of the intake valve for the engine cylinder are connected to receive pressurized fuel from the fuel rail. An engine control unit (ECU) receives signals from sensors on the internal combustion engine and is programmed to actuate the fuel injectors to deliver fuel to each engine cylinder over a full range of engine operating conditions. A port fuel injection system with high pressure and fast acting fuel injectors improves fuel delivery and performance over the full range of engine operating conditions.

A port injection engine, in which injected fuel readily vaporizes inside suction ports, includes: a suction port; a suction valve; and a port injector that injects fuel to an inner peripheral surface of the suction port. When the fuel is burned in a predetermined combustion cycle, an injection start of a fuel injection period is set within an end part of a valve opening period before the suction valve is fully closed, during a combustion cycle previous to the predetermined combustion cycle. The end part of the valve opening period is preferably set from 50° to 20° before the suction valve is fully closed at a crank angle.

A two-stroke engine includes a cylinder having a combustion chamber. The combustion chamber is delimited by a piston guided in a reciprocating manner in the cylinder and drives a crankshaft. A first intake channel opens into the crankcase interior. A transfer channel opens into the crankcase interior via a transfer window on a cylinder bore of the cylinder and via a passage opening. A second intake channel is provided for supplying scavenging air to the transfer channel. The first intake channel and the second intake channel are configured for supplying air. An injection valve configured for injecting the entire quantity of fuel to be supplied to the engine directly into the crankcase interior is disposed on the crankcase. A method for operating a two-stroke engine provides that the entire quantity of fuel to be supplied to the engine via a metering installation is supplied directly to the crankcase interior.

In at least some implementations, a charge forming device includes a body that has a throttle bore, a throttle valve associated with the throttle bore, a coupler and an actuator. The throttle has a valve head received within and movable relative to the throttle bore, and a valve shaft to which the valve head is coupled. The coupler is connected to the valve shaft and carries or includes a sensor element. And the actuator has a drive shaft coupled to the coupler so that rotation of the drive shaft is transmitted to the coupler and the valve shaft.

A port fuel injection system includes a fuel pump configured to produce a flow of pressurized liquid fuel at a pressure between 10 and 50 bar. A fuel rail is connected to receive the flow of pressurized liquid fuel from the fuel pump, the fuel rail. A plurality of fuel injectors, including one fuel injector positioned in the intake port of each engine cylinder upstream of the intake valve for the engine cylinder are connected to receive pressurized fuel from the fuel rail. An engine control unit (ECU) receives signals from sensors on the internal combustion engine and is programmed to actuate the fuel injectors to deliver fuel to each engine cylinder over a full range of engine operating conditions. A port fuel injection system with high pressure and fast acting fuel injectors improves fuel delivery and performance over the full range of engine operating conditions.

A fuel droplet micronizer serves to enhance and stabilize the power of the engines by effectively pulverizing fuel liquid to micro-droplets against flow electrification. The fuel droplet micronizer is composed of a micronization assistance part 30 formed from filaments, a mesh-like sheet or ribbon-like materials so forth made of metals, semiconductors, ceramics and glasses so on. The micronization assistance part 30 is installed between an ejection port 20 of an carburetor or the ejection apparatus and an intake valve 41 of the engine, whereby the fuel liquid ejected from the ejection port 20 of the carburetor or the ejection apparatus is smashed at the micronization assistance part 30, whereof impact facilitates micronization of fuel droplets by pulverizing and scattering.

A port injection engine, in which injected fuel readily vaporizes inside suction ports, includes: a suction port; a suction valve; and a port injector that injects fuel to an inner peripheral surface of the suction port. When the fuel is burned in a predetermined combustion cycle, an injection start of a fuel injection period is set within an end part of a valve opening period before the suction valve is fully closed, during a combustion cycle previous to the predetermined combustion cycle. The end part of the valve opening period is preferably set from 50° to 20° before the suction valve is fully closed at a crank angle.