An electric throttle device and a controlling system used for a portable gasoline engine may include a rotation shaft and a throttle mounted on the rotation shaft, the throttle working to open or close the intake channel, and may further include a power unit, a transmission unit in a transmission connection with the power unit, and a controller. The transmission unit is matched with the rotation shaft, and the controller includes a circuit driving module for driving the power unit to control the opening or closing of the throttle. The electric throttle device enables co-movement of the throttle and the choker as well as automatic opening or closing.

A method is for starting a combustion engine having a pull-rope starter. A fuel/air mixture is fed to the engine via an intake channel. The mixture is ignited by a spark plug. The combustion drives the piston downward and drives a crankshaft rotationally. The fuel system has a fuel channel opening into the intake channel. An electric fuel valve is open in its currentless state and closes a fuel channel only when an operating voltage is applied. An electronic control unit actuates the fuel valve and triggers an ignition spark and is utilized by a generator to supply energy to the control unit, the fuel valve and the ignition device. To prevent excessive enriching of the fuel/air mixture during starting, the energy, which is generated at the beginning of the rotation of the crankshaft, is used to first close the fuel valve before the control unit triggers an ignition spark.

There is provided an engine control device including (1) a regulator that regulates a flow rate per unit of time of exhaust gas discharged from an engine, and (2) a controller that, in cases in which an external temperature detection section detects an external temperature below freezing point, and a previous engine operation duration is shorter than a predetermined first duration, controls the regulator such that the flow rate rises to exceed a predetermined normal state, until a predetermined second duration has elapsed since the engine was started up.

An engine including a fuel tank, a carburetor, a speed control lever, and a transport valve. The carburetor includes a throttle valve movable between a first throttle position and a second throttle position. The speed control lever is coupled to the throttle valve and is movable between a first position corresponding to the first throttle position and a second position corresponding to the second throttle position. The transport valve is fluidly coupled between the fuel tank and the carburetor, and includes a valve element moveable between an open valve position allowing fuel flow between the fuel tank and the carburetor, and a closed valve position preventing fuel flow between the fuel tank and the carburetor. Movement of the speed control lever to the second position moves the valve element to the closed valve position to stop fluid flow between the fuel tank and the carburetor.

An electronic device for the ignition system of an engine, which may incorporate circuitry for voltage amplification via transformer action, while also containing circuitry for sensing operational parameters, circuitry for calculation of derived values from the sensed data or operational parameters, circuitry for storage of the data and derived values, circuitry for engine system control, and circuitry for the wireless communication of data and derived values.

An engine control device that regulates fuel to be supplied to an engine including: a starting fuel supply valve that supplies starting fuel to air to the engine or to an air-fuel mixture of air and fuel in starting the engine; an engine temperature detection unit that detects an engine temperature of the engine; an engine speed detection unit that detects the engine speed of the engine; and a control unit that controls the starting fuel supply valve to open and close to control the engine, in which the control unit controls an opening time of the starting fuel supply valve according to the engine temperature and the engine speed.

A hand-held power tool may include a housing, a power unit disposed within the housing and configured to operate at least in part in response to actuation of a trigger, a working assembly powered responsive to operation of the power unit, and an activation lever having an integrated lockout member. The activation lever may selectively engage a first fuel enrichment mode associated with startup of the power unit in a first range of ambient temperatures and a second fuel enrichment mode associated with startup of the power unit in a second range of ambient temperatures based on a position of the activation lever. Selective engagement of the first fuel enrichment mode or the second fuel enrichment mode may be enabled responsive to actuation of at least the lockout member and positioning of the activation lever.