| 摘要 |
PURPOSE:To simplify the tuning of a vibration isolating device in high and low frequency ranges by independently forming two vibration systems having four liquid chambers communicating mutually per pair through an orifice passage inside a rubber body inserted between a shaft member and an outer cylinder member. CONSTITUTION:A shaft member 1 moves relatively to an outer cylinder 2 to change the volume of each of liquid chambers 7-10, and liquid therefore moves between the chambers 7, 8 and 9, 10. In this case, since the liquid chambers 7, 8 are mutually communicated through an orifice passage 14 which is large in equivalent capacity, namely narrow in the cross sectional area of a passage and long in its length, they resonate in a low frequency range to make a large quantity of liquid pass through the passage 14. Thus a large loss factor can be obtained in the low frequency range having the frequency of 10Hz or so to effectively control the large amplitude vibration of an engine. On the other hand, since the liquid chambers 9, 10 are mutually communicated through an orifice passage 15 having small equivalent capacity, they resonate in the high frequency range to make a large quantity of liquid pass through the passage 15. Thus dynamic spring constant can be lessened in the high frequency range to effectively check the transmission of the minute vibration to a car body. |
