BRAKE PRESSURE CONTROL SYSTEM

摘要

A vehicle comprising sprung and unsprung parts is provided with a brake pressure reducing valve (10) controlled by a position sensing spring which applies to the control piston (12) a force (S) determined by the relative position of the sprung and unsprung parts. The sensing spring force (S) tends to move the control piston (12) in the direction to open the valve, and is opposed by an internal bias spring (18) which tends to close the valve. By suitable choice of piston areas A1 and A2 and spring forces increase (above cut-in pressure) in input pressure (P1) will always produce an increase in output pressure (P2) despite the reduction in sensing spring force (S) which will occur due to weight transfer.