| 摘要 |
PURPOSE: To arrange balance shafts in a crank casing without remarkably changing the crank easing by arranging first balance weights under a first bearing position, and arranging second balance weights under a second bearing position, and displacing the balance shafts side in relation to the center line of the crank shaft. CONSTITUTION: First balance weights 8a, 8b and second balance weights 9a, 9b are driven by a third crank arm 10a and an eighth crank arm 11a of a crank shaft 6, and the first balance weights 8a, 8b and the second balance weights 9a, 9b are supported by a bearing case in the cantilever condition using balance shafts 16, 17, 18, 19. The first balance weights 8a, 8b are arranged under a first bearing position 7, and the second balance weights 9a, 9b are arranged under a second bearing position 8, and the balance shafts 16-19 are displaced side in relation to the center line of the crank shaft 6. |
