Influence of constant pressure valve on boosting character of by-pass flow type ECHPS

The actuator in by-pass flow type electronically controlled hydraulic power steering (ECHPS) was solenoid valve. Boosting characters of ECHPS whose solenoid valves with and without constant pressure valve were analyzed and measured. The results show solenoid valve with or without constant pressure valve in the ECHPS engenders different characters that all of the pressure in the character within the constant pressure valve would attain high value of the rated system pressure but would not without constant pressure valve. For the safety factors of driving and designing of system, the character with constant pressure valve in the solenoid valve is better than this without constant pressure valve.