| 摘要 |
A drive unit (1) for a handheld working tool, such as a chain saw, trimmer or hedge trimmer, essentially comprising a housing part (2) with a fuel tank (3) and an engine unit (4) with a fuel supply unit (5) such as a carburetor (5), a muffler (6), and a crankcase scavenged combustion engine (7) with a cylinder (8), piston (15) and crankshaft. The engine (7) has at least one inlet port (9) located in the cylinder wall (10) of the engine and/or an adjacent part of the engine crankcase (11), and the engine's inlet duct (13) from the inlet port (9) up to the fuel supply unit (5) has a length longer than 1.8 times the engine cylinder stroke (18), preferably longer than 2.0 times the cylinder stroke (18). |
