| 摘要 |
A chain saw driven by a two-cycle opposed cylinder engine of simultaneous ignition type. The vibration energies generated in respective cylinders are offset by each other partly because the cylinders are made to oppose to each other, and partly because the ignitions of these cylinders take place simultaneously. Further, the opposed cylinder engine provides ample spaces above and below the cylinders. These spaces are conveniently used for accommodating intake system including a carburetor and so forth and exhaust system including a muffler and so forth. Sound shielding walls are disposed in the ample space around the cylinders so as to insulate the noise caused by the engine and, at the same time, to define a sufficiently large cooling air passage. |
