Electropneumatic control of braking force for railway vehicles - uses Wheatstone bridge to control differential amplifier comparators and then brake cylinder feed valves

摘要

The electropheunmatic circuit is for the control fo braking force, particularly on railway vehicles and it applies particularly to an electric regulator based on a normal Wheatstone bridge with one resistance representing the brake force and another the pressure. The centre of the brake force resistance is connected to an operational amplifier and of the pressure resistance to the negative of this amplifier. The amplifier output is joined to two comparators in turn connected to amplifiers and these feed coils of electrically operated valves. These valves control the supply of compressed air to the brake cylinders and the control is both sensitive and rapid acting.