Pipeline valve control system

Claim 2

A variable demand fluid delivery system including a first input pipe and second and third output pipes; each said output pipe having a valve therein responsive to a control signal for controlling the output flow in the respective pipe; and control means for applying a respective control signal to each said valve for controlling both said valves to maintain an adjustable predetermined flow rate in said second pipe and with the excess going to said third pipe as the input flow rate in said first pipe varies; one of said valves opening as the control signal applied thereto increases and the other said valve closing as the control signal applied thereto increases; said control means including a controller providing a variable signal whose amplitude is representative of said predetermined flow rate for said second pipe and first and second constant amplitude signal sources providing signals of respectively different amplitude; and said control means at times coupling said controller to said one valve and said first signal source to said other valve and at other times coupling said controller to said other valve and said second signal source to said one valve.

Claim 3

The system of claim 1 in which said valves are both responsive to an electric current and both said first and second signal sources are constant current sources.

Claim 4

The system of claim 1 wherein both said first and second signal sources when connected at different times respectively to said other valve and said one valve are effective to control said valves to substantially their open positions.

Claim 5

The system of claim 2 in which said control means further includes a first electrical contactor which is open except when said one valve is fully open and a second electrical contactor which is closed except when said other valve is fully open, and means responsive to both said contactors being closed for connecting said one valve to said second signal source and said other valve to said controller.

Claim 6

The system of claim 4 in which said responsive means includes an electromagnetic relay.

Claim 7

A control system for regulating the flow of a fluid from a source to two outlets in such manner as to maintain an adjustable predetermined flow in a first of said outlets while the excess flow goes to the second outlet comprising: an electrically controllable valve for each outlet regulating the flow from the respective outlet, each said valve being operable between open and closed positions in response to the magnitude of an electrical signal applied thereto; said valve for said first outlet opening with an increase in signal and said valve for said second outlet closing in response to an increase in signal; a controller for providing an electrical signal representative of the desired flow rate for said first outlet; means for controlling the amplitude of signal provided by said controller; a first signal source providing a first signal of constant amplitude for operating said valve of said second outlet to a substantially fully open condition when applied thereto; a second signal source providing a second signal of constant amplitude for operating said valve of said first outlet to fully open condition when applied thereto; means responsive to said two valves foR coupling said controller to said valve for said first outlet and said second signal source to said valve for said first outlet until said control signal becomes of such increased magnitude as to fully open said valve for said first outlet; and said responsive means thereafter coupling said controller to said valve for said second outlet and also coupling said second signal source to said valve for said second outlet until said control signal becomes of such reduced magnitude as to operate said valve for said second outlet to its fully open condition.

Claim 8

A control system for regulating the flow of a fluid from a source to two outlets in such manner as to maintain an adjustable predetermined flow in a first of said outlets while the excess flow goes to the second outlet comprising: an electrically controllable valve for each outlet regulating the flow from the respective outlet, each said valve being operable between open and closed positions in response to the magnitude of an electrical signal applied thereto; said valve for said first outlet opening with an increase in signal and said valve for said second outlet closing in response to an increase in signal; a controller for providing an electrical signal representative of the desired flow rate for said first outlet; means for controlling the amplitude of signal provided by said controller; a first signal source providing a first signal of constant amplitude for operating said valve of said second outlet to a substantially fully open condition when applied thereto; a second signal source providing a second signal of constant amplitude for operating said valve of said first outlet to fully open condition when applied thereto; means responsive to said two valves foR coupling said controller to said valve for said first outlet and said second signal source to said valve for said first outlet until said control signal becomes of such increased magnitude as to fully open said valve for said first outlet; and said responsive means thereafter coupling said controller to said valve for said second outlet and also coupling said second signal source to said valve for said second outlet until said control signal becomes of such reduced magnitude as to operate said valve for said second outlet to its fully open condition.

Claim 9

A control system for regulating the flow of a fluid from a source to two outlets in such manner as to maintain an adjustable predetermined flow rate in a first of said outlets while the excess goes to the second outlet, said system comprising: a control signal source generating a control signal of continuously variable amplitude representative of said predetermined flow rate; first and second continuously variable control valves operatively associated with said first and second outlets respectively to regulate the flow from each such outlet and with each said control valve being responsive to the amplitude of a signal applied thereto; said first valve being of the type which opens with increasing amplitude of the signal applied thereto and said second valve being of the type which closes with increasing amplitude of the signal applied thereto; control means responsive to the operated conditions of said control valves and being operable between distinctively different first and second conditions; said control means in its first condition operatively connecting said control signal to said first control valve while concurrently maintaining said second control valve in a substantially fully open position; and said control means in its second condition operatively connecting said control signal to said second control valve while concurrently maintaining said first control valve in a substantially fully open position.

Claim 10

A control system for regulating the flow of a fluid from a source to two outlets in such manner as to maintain an adjustable predetermined flow rate in a first of said outlets while the excess goes to the second outlet, said system comprising: a control signal source generating a control signal of continuously variable amplitude representative of said predetermined flow rate; first and second continuously variable control valves operatively associated with said first and second outlets respectively to regulate the flow from each such outlet and with each said control valve being responsive to the amplitude of a signal applied thereto; said first valve being of the type which opens with increasing amplitude of the signal applied thereto and said second valve being of the type which closes with increasing amplitude of the signal applied thereto; control means responsive to the operated conditions of said control valves and being operable between distinctively different first and second conditions; said control means in its first condition operatively connecting said control signal to said first control valve while concurrently maintaining said second control valve in a substantially fully open position; and said control means in its second condition operatively connecting said control signal to said second control valve while concurrently maintaining said first control valve in a substantially fully open position.