Two-stroke engine for hand-held power tool

摘要

The engine has a cylinder casing (1) closed by a crankcase cover (11), and a crankshaft (20) in shaft bearings (17). The casing and cover contain half-shells (14,15) to receive the shaft bearing. There are transfer channels (8,9) in the cylinder wall running from the crankcase (7) to the combustion chamber (2), passing through the half-shells. The half-shells have a diameter (H) which is significantly greater than the external diameter (W) of the shaft bearing. A support shell (25) is fitted in the space between them, closing the gaps (18,19) in the bearing surface of the half-shells.