In an air intake-type two-stroke engine 10, an exhaust port 20, a scavenging port 22,etc. are opened and closed by a piston 12. A fuel injection valve 60 is disposed at an upper end portion 24a of a scavenging passage 24. The fuel injection valve 60 is preferably arranged with its axis Lax directed toward the scavenging port 22. The fuel injection timing is set to the latter half of the scavenging process or the latter half of the combustion process.

Handheld construction equipment may include a crankcase scavenged combustion engine arranged to drive a work tool where a fuel injector is configured to provide a controlled amount of fuel into an air and fuel intake flow of the combustion engine, and where an idling air flow channel is arranged to connect with the air and fuel intake flow of the combustion engine in connection to the fuel injector.

A crankcase scavenged two-stroke engine (1) is disclosed comprising a cylinder (2), a crankcase (5), a crankshaft (10), and a piston (3). The piston (3) comprises a first face (F1) forming a delimiting surface of a combustion chamber (4) and a second face (F2) forming a delimiting surface of a crankcase volume (V). The engine (1) comprises a pump chamber (8) with an aperture (18) 2024/072312 facing the second face (F2) of the piston (3). The piston (3) comprises a section (13) configured to protrude into the pump chamber (8) via the aperture (18) to delimit the pump chamber (8) from the crankcase volume (V) when the piston (3) is at a predetermined position between the top dead centre and the bottom dead centre. The present disclosure further relates to a handheld power tool (20).

A crankcase scavenged two-stroke engine (1) is disclosed comprising a cylinder (2), a crankcase (5), a crankshaft (10), and a piston (3). The piston (3) comprises a first face (F1) forming a delimiting surface of a combustion chamber (4) and a second face (F2) forming a delimiting surface of a crankcase volume (V). The engine (1) comprises a pump chamber (8) with an aperture (18) 2024/072312 facing the second face (F2) of the piston (3). The piston (3) comprises a section (13) configured to protrude into the pump chamber (8) via the aperture (18) to delimit the pump chamber (8) from the crankcase volume (V) when the piston (3) is at a predetermined position between the top dead centre and the bottom dead centre. The present disclosure further relates to a handheld power tool (20).