| 摘要 |
The fluid flow rate from a drain tank (32) is regulated by cooperatively modulating first and second valves (42, 44) arranged in parallel flow relation to allocate fluid flow to first and second fluid sinks (38, 40). …<??>First and second parallel acting signal generators (50, 52) detect the fluid level in the drain tank (32) and generate fluid level indicator signals. The first signal generator's signal is normally transmitted to the first valve (42) which modulates in response thereto to maintain the desired drain tank fluid level. The second signal generator (52) normally provides a drain tank level indication signal to the second valve (44) which modulates for signals indicative of drain tank fluid levels greater than a predetermined height. Signal monitors (66, 68) provide means for detecting erroneous signals generated by the first and second signal generators (50, 52). If an erroneous signal, as indicated by a signal being out of a predetermined range, from one signal generator is monitored, transmission of that signal to its respective valve is obstructed and the other signal generator's signal is transmitted to both valves (42, 44). |
