| 摘要 |
PURPOSE:To effectively damp vibration due to shaking by an engine, by setting the ratio of lengths of a pair of orifices to a value from 2.5-9 so that a frequency at which the damping force is maximum is made to fall in a low frequency range in which the shaking of the engine occures. CONSTITUTION:Diaphragms 4, 5 and partition plates 6, 7 which are secured, respectively to a base plate 1 on the power unit side and a base plate 2 on a vehicle side, define a first subchamber 8 and a second subchamber. A pair of orifices 15, 14 having substantially equal crosssectional areas and having lengths which are set at a ratio from 2.5-9, are formed in the partition plates 6, 7. As a result the mass of fluid in one orifice 14 having a longer length resonates in a lower frequency range to give a large damping force while the mass of fluid in the other orifice 15 having a shorter length resonates in a higher frequency range to give a damping force having the same magnitude as that of the former damping force, thereby it is possible to effectively damp vibration due to shaking by an engine. |
