| 摘要 |
PURPOSE:To improve the comfortableness to drive a 3-step damping force variable car and its operating stability by determining environmental conditions based on upper and lower oscillation acceleration, oscillation acceleration near the resonant frequency on a spring, and car speed signals in a suspension for the car and controlling them based on the size of the oscillation acceleration signal. CONSTITUTION:One of upper and lower oscillation acceleration signals G passes through a low pass filter 3 and is input to the AND logic circuit 11 of a logic circuit 9 through a bandpass filter 5, comparator 7, and delay circuit 8 as the frequency component signal Gf near the resonant frequency on a car body spring together with a car speed signal V. In addition, the other signal G is input to a NOT circuit 10 from the low pass filter 3 through a comparator 4 and a delay circuit 6. Thus, the logic circuit 9 classifies running and road surface states into four-step environmental conditions. When the oscillation acceleration signal G is low, the circuit outputs normal N or hard H signals and when it is high, the circuit outputs soft S or normal N signals, and then controls a damper 17 in three steps. As a result, control is enabled according to the road surface and running states. |
