A Study on the Performance Characteristics of Variable Valve for Reverse Continuous Damper

Nowadays, a passenger car suspension must has high performance criteria with light weight, low cost, and low energy consumption. Pilot controlled proportional valve is designed and analyzed to get small pressure change rate after blow-off, and to get a fast response of the damper, a reverse damping mechanism is adapted. The reverse continuous variable damper is designed as a HS-SH damper which offers good body control with reduced transferred input force from the tire, compared with any other type of suspension system. The damper structure is designed, so that rebound and compression damping forces can be tuned independently, of which the variable valve is placed externally. The rate of pressure change with respect to the flow rate after blow-off becomes smooth when the fixed orifice size increases, which means that the blow-off slope is controllable using the fixed orifice size. Damping forces are measured with the change of the solenoid current at the different piston velocities to confirm the maximum hysteresis of 20 N, linearity, and variance of damping force. The damping force variance is wide and continuous, and is controlled by the spool opening, of which scheme is usually adapted in proportional valves. The reverse continuous variable damper developed in this study is expected to be utilized in the semi-active suspension systems in passenger cars after its performance and simplicity of the design is confirmed through a real car test.

Authors:

• Se Kyung Oh
• Young Hwan Yoon
• Ary Bachtiar Krishna

Keywords:

• Blow-off
• damping force
• pilot controlledproportional valve
• reverse continuous damper.

References:

[1] D. C. Karnopp, M. J. Grosby, and R. A. Harward, , "Vibration control
using semi-active force generator", ASME, J. of engineering for industry,
vol. 98, May 1974
[2] S. Buma, H. Kondo, K. Sato, and T. Aburaya, "Development of the
Toyota Active Control Suspension for the 1989 Celica", Toyota technical
paper, Vol. 40, No. 2. 1990
[3] S. Buma, H. Satou, T. Yonekawa, Y. Ohnuma, K. Hattori, and M.
Shiguhara, "Synthesis and Development of the Active Control
Suspension", JSME (C) Vol. 57, No. 534, 1991.
[4] D. Knutson, "Selection and Design of Electrohydraulic Valves for
Electrically-Controlled Automotive Suspension System", SAE 912500,
1991
[5] F. Wobner, P. Causeman, "Continuously Adjustable Shock Absorber",
AVEC 92(1992.9), 923055, 1992
[6] J. Emura, S. Kakizaki, F. Yamaoka, and M. Nakamura, "Development of
the Semi-Active Suspension System Based on the Sky-hook Damper
Theory", SAE 940863, 1994.