Rotary valve in power steering system in vehicle

摘要

The power assistance system is used for the steering of a road vehicle. The system incorporates a rotary disc valve (1). There are ports in its casing (2) connected to hydraulic circuits for an actuator or servomotor and a pump supplying hydraulic fluid under pressure. The input shaft (5) is connected to an inner valve sleeve (4) with ports. The input shaft is also connected to a thin shaft (12) which allows a small amount of torsional deformation. The other end of this shaft is connected to the output shaft (10). There is an outer valve sleeve (8) connected to the output shaft and moving through a small angle with respect to the inner sleeve due to elastic deformation of the thin shaft.