VALVE

摘要

A fluid flow control valve island (9), for example for use in sequentially controlling pneumatic actuators of automated production machinery, comprises a plurality of sets (one of which is designated 14) of four bistable 2/2 control valves a, b, c and d, a programmable controller (10) which processes control signals from an external programmable logic controller (PLC) (11), and a memory element (13). The controller (10) is pre-programmed with a program downloaded from an external PC (12) and stored in the memory element (13), the program identifying the respective predetermined valve type to be simulated by each set of 2/2 valves a, b, c and d. The controller (10) generates from signals from the PLC (11) respective outputs to each of the four valves a, b, c and d in a set so as to actuate one or more of those four valves and thus switch that set from one mode of the predetermined valve type simulated to its other, or another, mode. The invention thus provides a universal valve island that may be programmed by the manufacturer or the user to simulate a multitude of selected, differing, valve types, including 2/2 NO or NC, 3/2 NO or NC, 5/2, 5/3 COP, 5/3 COE and 5/3 APB types without having to mechanically reconfigure the valves on the island (9).