FLUID FLOW CONTROL VALVES

摘要

A fluid flow control valve system has a plurality of pairs of 3 port, 2 position (3/2) control valves (6, 6') each valve being movable between its two positions by a pair of electrically-operable actuators (1, 2). A logic controller selectively generates electrical control signals for independently controlling operation of the pairs of 3/2 control valves, and a circuit means (11) is associated with each 3/2 control valve pair (6, 6') to receive the control signals and provide electrical outputs to either of the actuators (1, 2) of each 3/2 control valve of each pair. Variable switch means (14) forming part of the circuit means (11) pre-select the actuators (1, 2) to which the output is applied. Varying the switch means (14) programmes the fluid output mode of each 3/2 control valve pair to provide any one of a number of different effective valve types.