| 摘要 |
PURPOSE:To provide the cooling air intake shroud opening structure of an air-cooled internal combustion engine excellent in sound insulating performance. CONSTITUTION:A synthetic resin made shroud 20 for covering an internal combustion engine 3 and cooling fans 19 is formed of a cylinder side shroud 21 for covering the cooling fans 19 and a cylinder 14, a head side shroud 22 for covering a cylinder head 15, and a shroud outside plate 23 for covering the outside of the cylinder side shroud 21. A cylindrical opening 25 is formed at the cylinder side shroud 21, and an inner louver 26 is formed at the cylindrical opening 25. The inner louver 26 is formed by disposing wide fins 27 inclining them from the rear to the front toward the outside from the inside at large spaces apart over the longitudinal direction. A cylindrical opening 28 protruding outward is formed also at the shroud outside plate 23, and an outer louver 29 is formed at the cylindrical opening 28. The outer louver 29 is formed by disposing relatively narrow fins 30 inclining them from above to below toward the outside from the inside at narrow spaces apart over the vertical direction. |
