A fuel feed unit has a base body with an intake channel section, into which a fuel opening opens. A partition wall section divides the intake channel section into a mixture channel and an air channel. The wall section has a recess in which the throttle flap at least partially lies in an end position. The wall section has, upstream of the recess, a continuous surface facing the mixture channel and which has lateral sections adjacent to the channel wall and a middle section running between the lateral sections. The lateral sections have, upstream of the throttle flap, a separation edge for the flow. In the end position, the side of the throttle flap facing the mixture channel defines a reference plane which divides the unit into a first region and a second region. The lateral sections extend, at least directly upstream of the recess, into the second region.

An engine assembly includes: a two-stroke internal combustion engine; a turbocharger operatively connected to the engine, the turbocharger having a compressor and an exhaust turbine; an intake pipe fluidly connected to the engine and to the compressor of the turbocharger; an exhaust tuned pipe fluidly connected to the engine and to the exhaust turbine of the turbocharger; a temperature sensor configured to generate a signal representative of a temperature of exhaust gas flowing within the exhaust tuned pipe; and a controller. The controller is configured to: determine a boost target pressure of the turbocharger based in part on the signal generated by the temperature sensor; and control the turbocharger to provide the boost target pressure to the engine. Methods for controlling an engine are also provided.

Provided is a two-stroke internal combustion engine, including: a fuel injection valve configured to supply a fuel into a crank chamber; an intake passage configured to allow only air to be sucked thereinto under a negative pressure generated when a piston is actuated; and a scavenging passage that allows communication between the crank chamber and a combustion chamber. Further, air passing through the intake passage is introduced into the scavenging passage, and air stagnant in the scavenging passage at end of air suction contributes to scavenging.

An air-leading type, stratified scavenging two-stroke engine. The engine including a cylinder member and a crankcase joined therewith has an intake passage, an exhaust passage, first and second scavenging passages, a communicating portion and an air passage. The intake passage, the exhaust passage and the air passage are formed in the cylinder member. The first and the second scavenging passages each has a cylinder member-side passage and a crankcase-side passage. The cylinder member-side passages of both of the first and the second scavenging passages communicate with each other via the communicating portion. The air passage is connected to the cylinder member-side passage of the first scavenging passage. In the engine, air for pre-scavenging is introduced from the air passage through a check valve into the cylinder member-side passage of the first scavenging passage, and a part of the introduced air flows into the second scavenging passage through the communicating portion.

A method for controlling a two-stroke engine operatively connected to a turbocharger, the turbocharger being in fluid communication with the engine to provide a boost pressure thereto, the method including: comparing one of (i) an actual power output of the engine; and (ii) an exhaust temperature representative of an actual temperature of exhaust gas being discharged by the engine, with a corresponding threshold value thereof; in response to the one of the actual power output of the engine and the exhaust temperature being less than the corresponding threshold value: determining a corrective amount of boost pressure to add to the boost pressure of the turbocharger; and controlling the turbocharger to increase the boost pressure of the turbocharger by the corrective amount. Another method for controlling a two-stroke engine operatively connected to a turbocharger is also disclosed.

A fuel supply device has a base body, in which an intake channel section is formed. At least one adjustable throttle element for controlling the free flow cross section of the intake channel section is provided. At least one fuel opening opens into the intake channel section. A partition wall section is arranged in the intake channel section upstream of the throttle element. The partition wall section and the throttle element divide, in a completely open position of the throttle element, the intake channel section upstream of the throttle element into a mixture channel, into which the fuel opening feeds fuel, and an air channel. In order to improve the cooling of the fuel supply device, the partition wall section has at least one element for increasing the surface area within the mixture channel.

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.

A fuel feed unit has a base body with an intake channel section, into which a fuel opening opens. A partition wall section divides the intake channel section into a mixture channel and an air channel. The wall section has a recess in which the throttle flap at least partially lies in an end position. The wall section has, upstream of the recess, a continuous surface facing the mixture channel and which has lateral sections adjacent to the channel wall and a middle section running between the lateral sections. The lateral sections have, upstream of the throttle flap, a separation edge for the flow. In the end position, the side of the throttle flap facing the mixture channel defines a reference plane which divides the unit into a first region and a second region. The lateral sections extend, at least directly upstream of the recess, into the second region.

A mixture formation unit has a base body in which an intake channel section is formed. The intake channel section extends from a first end side of the base body to a second end side of the base body. The mixture formation unit has at least one rectilinearly extending channel which opens into the intake channel section. The channel opens at the first end side of the base body. The mixture formation unit is preferably provided for a two stroke engine whose intake channel is divided downstream of the mixture formation unit into a mixture channel and an air channel.

A two-stroke engine (1) is disclosed comprising a cylinder (2), a piston (3) arranged to reciprocate in the cylinder (2), a crankcase (5), a fuel injector (7) configured to inject fuel into the crankcase (5), an air inlet (9) connected to the crankcase (5), and a stratified scavenging intake (11) connected to the cylinder (2). The engine (1) comprises a throttle (13) configured to control the amount of air supplied to the air inlet (9) and to the stratified scavenging intake (11). The present disclosure further relates to handheld power tool (50) comprising an engine (1).