PURPOSE: To provide a vehicle vibration reducing device capable of improving a domain where the characteristic of transmitting vibration are deteriorated by the use of a dynamic damper unit attached to the unsprung mass, effectively performing vibration control in a wide frequency range, thereby improving ride comfort.
CONSTITUTION: A dynamic damper unit 40 consisting of a spring 31, a mass 33, a variable damper 35, and an actuator 37 for changing the damping coefficient of the variable damper 35 is attached to an upper arm 11. High-frequency vibration inputting from a road surface projection 45 to a suspension is detected by a vibration acceleration sensor 47. The ECU 50 selects a frequency range where the reduction of vehicle vibration is desirable especially, or necessary by means of range-judgement using the difference in the magnitude of vehicle vibration, the magnitude ratio, etc., in two frequency ranges, sends a signal to a driving unit 51 so that the damping force of the damper corresponds to the selected frequency range, to actuate the actuator 37.
ISHIKAWA HIROSHI
TAKEDA MASAYOSHI
DOI SHUNICHI
ISHIGURO RIKUO
TAKEI KAZUTAKA
TOYOTA CENTRAL RES & DEV