| 摘要 |
PURPOSE:To greatly reduce the vibration of a floor by causing a frequency at which the dynamic spring constant of a supporting device for a power unit is lowered most and a frequency at which the phase of the vibration transmission of the supporting device is at its maximum to almost agree with the idling frequency of the power unit. CONSTITUTION:A supporting device 1 for a power unit has an elastic body 4 interposed between an inner tube 2 and an outer tube 3. A circular channel 8 communicated with both a main fluid chamber 6 and an auxiliary fluid chamber 7 is formed on the outside face of the axial center portion of the elastic body 4 and orifice formation bodies 9a to 9d forming two orifices 10, 11 and each made of an insulator are fitted over the circular channel 8. Pairs of electrode plates 12a, 12b, 13a, 13b are fixed on the respective inner faces of the orifices 10, 11 and connected to respective high voltage power sources 16a, 16b each of which applies a voltage corresponding to a control signal supplied from a controller 15. A frequency at which the dynamic spring constant of the supporting device 1 is lowered most and a frequency at which the phase of the vibration transmission of the supporting device 1 is at its maximum are both made to almost agree with the idling frequency of the power unit. |
