| 摘要 |
In an endothermic engine there are two dynamic balancing shafts driven in rotation in respectively opposite directions, at a speed twice that of the rate of rotation of the crankshaft. The dynamic balancing shafts are driven by a toothed belt transmission (1), comprising a driving pulley (2) keyed on the crankshaft, two driven pulleys (3, 4) keyed on the balancing shafts and a tensioning pulley (5) rotatably engaged with the base. The pulleys (2, 3, 4, 5) are connected together by a belt (6) having an internal (9) and external (10) toothing with a toothing pitch (P) equal to 7.5 mm, and provided with a resistant insert (7) formed by glass fibre cords (8) having a diameter equal to 0.9 mm.
|
