Improvements in and relating to control valves.

摘要

A control valve, in particular a brake control valve for fluid pressure operated vehicle braking systems, in which the operating effort is applied to a control element of the valve via a travel or transmission spring assembly (9) and in which travel hysteresis is reduced by introducing between the transmission spring or springs (9) and a control element (6, 8) of the valve, a predetermined friction load to oppose travel of the spring or springs. The friction load is generated by friction rings fitted or bearing upon a tie rod running in a bore of the control element.