| 摘要 |
PROBLEM TO BE SOLVED: To suppress generation of vibration noise in a vehicle even when vibrating force is added to the vehicle by change in pressure of a fluid chamber so as to reduce the vibration noise. SOLUTION: The negative pressure from a negative pressure pump 27 is periodically supplied by controlling a duty control valve 24 with respect to an air chamber 21 provided on a mount 6 so as to make it to function it as a vibration for a vehicle. Vibrating force is controlled while the duty ratio of the duty control valve 24 is kept within a fixed range by adjusting the pipe diameter of a negative pressure lead-in pipe 25 using a pipe diameter adjusting device 28. Therefore, it is not necessary to drive the duty control valve 24 at a low duty ratio or a high duty ratio so that generation of noise in a vehicle can be suppressed. |
