Method and apparatus for providing a determined ratio of process fluids

• US 6,752,166 B2
• Filed: 05/23/2002
• Issued: 06/22/2004
• Est. Priority Date: 05/24/2001
• Status: Expired due to Term

• Current Assignee: Brooks Instrument LLC (Illinois Tool Works Inc.)
• Original Assignee: Celerity Incorporated (ICHOR Holdings, Ltd.)
• Inventors: Valentine, William S., Lull, John M.
• Primary Examiner(s): Krishnamurthy, Ramesh
• Application Number:
  US10/154,433
• Publication Number:
  US 20020179148A1
• Time in Patent Office: 761 Days
• Field of Search: 137/9, 137/12, 137/101.19, 137/118.04, 137/118.06, 137/486, 137/487.5, 137/557, 137/883, 137/2, 137/597, 118/715, 118/692, 438/935
• US Class Current: 137/9
• CPC Class Codes: G05D 11/132 by controlling the flow of the individual components G05D11/133 takes precedence
• CPC Class Codes: G05D 7/0664 the plurality of throttling means being arranged for the control of a plurality of diverging flows from a single flow G05D7/0652 takes precedence; ratio control G05D11/13
• CPC Class Codes: Y10T 137/0324 With control of flow by a condition or characteristic of a fluid
• CPC Class Codes: Y10T 137/0363 For producing proportionate flow
• CPC Class Codes: Y10T 137/0379 By fluid pressure
• CPC Class Codes: Y10T 137/0396 Involving pressure control
• CPC Class Codes: Y10T 137/7759 Responsive to change in rate of fluid flow
• CPC Class Codes: Y10T 137/7761 Electrically actuated valve
• CPC Class Codes: Y10T 137/87249 Multiple inlet with multiple outlet
• CPC Class Codes: Y10T 137/87877 Single inlet with multiple distinctly valved outlets

Abstract

A fluid flow control system that includes a fluid inlet to receive a flow of process fluid and a plurality of fluid outlets. The plurality of fluid outlets include a first fluid outlet and at least one second fluid outlet. The first fluid outlet provides a first predetermined portion of the flow of process fluid, and the at least one second fluid outlet provides the remaining portion of the flow of process fluid. In one embodiment the control system includes a pressure transducer, first and second multipliers, and first and second flow controllers. The first multiplier multiplies a pressure signal received from the pressure transducer by a first setpoint to control a first flow controller that provides the first predetermined portion of the flow of process fluid. The second multiplier multiplies the pressure signal by a second setpoint to control a second flow controller that provides the remaining portion.

Claims

1. A fluid flow control system, comprising:

a fluid inlet to receive a flow of process fluid;

a plurality of fluid outlets, the plurality of fluid outlets including a first fluid outlet and at least one second fluid outlet, the first fluid outlet providing a first predetermined portion of the flow of process fluid, and the at least one second fluid outlet providing a remaining portion of the flow of process fluid;

a pressure transducer, to measure a pressure of the process fluid in the fluid inlet and provide a pressure signal indicative of the pressure of the process fluid;

a first multiplier to receive the pressure signal and a first setpoint indicative of the first predetermined portion of the flow of process fluid to be provided by the first fluid outlet and multiply the pressure signal by the first setpoint to provide a first multiplied setpoint;

a first flow controller, fluidly coupled to the fluid inlet and the first fluid outlet, to receive the first multiplied setpoint and provide the first predetermined portion of the flow of process fluid to the first fluid outlet based upon the first multiplied setpoint;

a second multiplier to receive the pressure signal and a second setpoint indicative of the remaining portion of the flow of process fluid to be provided by the at least one second fluid outlet and multiply the pressure signal by the second setpoint to provide a second multiplied setpoint; and

a second flow controller, fluidly coupled to the fluid inlet and the at least one second fluid outlet, to receive the second multiplied setpoint and provide the remaining portion of the flow of process fluid to the at least one second fluid outlet based upon the second multiplied setpoint.

2. The fluid flow controller of claim 1, further comprising:

a subtraction circuit to receive the first setpoint, subtract the first setpoint from a value indicative of a full-scale flow of process fluid to provide the second setpoint to the second multiplier.

3. The fluid flow control system of claim 1, further comprising:

a plurality of fluid supply flow controllers each having a fluid inlet and a fluid outlet, the fluid inlet of each respective fluid supply flow controller being fluidly coupled to a respective supply of fluid, each respective fluid supply flow controller receiving a respective setpoint indicative of an amount of the respective fluid to be provided at the fluid outlet of the respective fluid supply controller, and the fluid output of each respective fluid supply controller being fluidly coupled to the fluid inlet to provide the flow of process fluid; and

a process controller, to provide the respective setpoint to each respective fluid supply controller, and to provide the first and second setpoints to the first and second multipliers, respectively.

4. The fluid flow control system of claim 3, wherein the first and second flow controllers are tuned to have a similar response on a known fluid.

5. A fluid flow control system, comprising:

a fluid inlet to receive a flow of process fluid; and

a plurality of fluid outlets, the plurality of fluid outlets including a first fluid outlet and at least one second fluid outlet, the first fluid outlet providing a first predetermined portion of the flow of process fluid, and the at least one second fluid outlet providing a remaining portion of the flow of process fluid;

wherein the at least one second fluid outlet includes a plurality of second fluid outlets that together provide the remaining portion of the flow of process fluid, the fluid flow control system further comprising;

a pressure transducer, to measure a pressure of the process fluid in the fluid inlet and provide a pressure signal indicative of the pressure of the process fluid;

a first multiplier to receive the pressure signal and a first setpoint indicative of the first predetermined portion of the flow of process fluid to be provided by the first fluid outlet and multiply the pressure by the first setpoint to provide a first multiplied setpoint;

a first flow controller, fluidly coupled to the fluid inlet and the first fluid outlet, to receive the first multiplied setpoint and provide the first predetermined portion of the flow of process fluid to the first fluid outlet based upon the first multiplied setpoint;

a plurality of second multipliers, each corresponding to a respective second fluid outlet of the plurality of second fluid outlets, to receive the pressure signal and a respective second setpoint indicative of a respective second portion of the flow of process fluid to be provided by the respective second fluid outlet and multiply the pressure signal by the respective second setpoint to provide a respective second multiplied setpoint; and

a plurality of second flow controllers, fluidly coupled to the fluid inlet and a respective second fluid outlet, to receive a respective second multiplied setpoint and provide a respective second portion of the flow of process fluid based upon the second multiplied setpoint.

6. The fluid flow control system of claim 5, wherein the first flow controller and the plurality of second flow controllers are tuned to have a similar response on a known fluid.

7. A method of controlling a flow of process fluid, comprising acts of:

receiving the flow of process fluid at a fluid inlet;

providing a first predetermined portion of the flow of process fluid to a first fluid outlet; and

providing a remaining portion of the flow of process fluid to at least one second fluid outlet;

the method further comprising acts of;

measuring a pressure of the process fluid in the fluid inlet;

receiving a first setpoint indicative of the first predetermined portion of the flow of process fluid to be provided to the first fluid outlet;

multiplying the first setpoint by the pressure of the process fluid to determine a first multiplied setpoint; and

directing a first flow controller to provide the first predetermined portion of the flow of process fluid to the first fluid outlet based upon the first multiplied setpoint.

8. The method of claim 7, further comprising acts of:

multiplying the pressure of the process fluid by a second setpoint indicative of the remaining portion of the flow of process fluid to be provided to the at least one second fluid outlet to determine a second multiplied setpoint; and

directing a second flow controller to provide the remaining portion of the flow of process fluid to the at least one second fluid outlet based upon the second multiplied setpoint.

9. The method of claim 8, further comprising an act of:

tuning the first and second flow controllers to have a similar response on a known fluid.

10. The method of claim 8, further comprising acts of:

receiving a value indicative of the flow of process fluid received at the fluid inlet; and

determining the second setpoint by subtracting the first setpoint from the value indicative of a full-scale flow of process fluid received at the fluid inlet.

11. The method of claim 10, further comprising an act of:

tuning the first and second flow controllers to have a similar response on a known fluid.

12. The method of claim 11, wherein the first and second flow controllers each include a flow sensor and a valve, the method further comprising an act of:

minimizing affects of pressure transients on the flow sensor by disposing the flow sensor downstream of the valve in each of the first and second flow controllers.

13. A method of, controlling a flow of process fluid, comprising acts of:

receiving the flow of process fluid at a fluid inlet;

providing a first predetermined portion of the flow of process fluid to a first fluid outlet; and

providing a remaining portion of the flow of process fluid to at least one second fluid outlet;

wherein the at least one second fluid outlet includes a plurality of second fluid outlets that together provide the remaining portion of the flow of process fluid, the method further comprising acts of;

measuring a pressure of the process fluid in the fluid inlet;

receiving a first setpoint indicative of the first predetermined portion of the flow of process fluid to be provided to the first fluid outlet;

multiplying the first setpoint by the pressure of the process fluid to determine a first multiplied setpoint;

directing a first flow controller to provide the first predetermined portion of the flow of process fluid to the first fluid outlet based upon the first multiplied setpoint;

receiving a plurality of second setpoints, each corresponding to a second fluid outlet of the plurality of second fluid outlets;

multiplying each respective second setpoint by the pressure of the process fluid to respectively determine a plurality of respective second multiplied setpoints; and

directing each of a plurality of second flow controllers that respectively correspond to a respective second fluid outlet of the plurality of second fluid outlets to provide a respective second portion of the flow of process fluid based upon each of the respective second multiplied setpoints.

14. The method of claim 13, further comprising an act of:

tuning the first flow controller and each of the plurality of second flow controllers to have a similar response on a known fluid.

15. A fluid flow controller to provide a flow of process fluid to a plurality of device inlets, comprising:

a fluid inlet to receive the flow of process fluid;

a plurality of fluid outlets to provide the flow of process fluid to the plurality of device inlets, the plurality of fluid outlets including a first fluid outlet and at least one additional fluid outlet;

a first input to receive a first signal indicative of an amount of the process fluid that is received at the fluid inlet;

a second input to receive a second signal indicative of a first predetermined portion of the amount of the process fluid that is to be provided to the first fluid outlet, with a remaining portion of the amount of the process fluid being provided to the at least one additional fluid outlet;

a first multiplier, to receive the first signal and the second signal, multiply the first signal by the second signal to provide a first multiplied signal; and

a first flow controller, fluidly coupled to the fluid inlet and the first fluid outlet, to receive the first multiplied signal and provide the first predetermined portion of the amount of the process fluid to the first fluid outlet based upon the first multiplied signal;

wherein the first signal identifies a pressure of the process fluid received at the fluid inlet.

16. A The fluid flow controller to provide a flow of process fluid to a plurality of device inlets, comprising:

a fluid inlet to receive the flow of process fluid;

a plurality of fluid outlets to provide the flow of process fluid to the plurality of device inlets, the plurality of fluid outlets including a first fluid outlet and at least one additional fluid outlet;

a first input to receive a first signal indicative of an amount of the process fluid that is received at the fluid inlet;

a second input to receive a second signal indicative of a first predetermined portion of the amount of the process fluid that is to be provided to the first fluid outlet, with a remaining portion of the amount of the process fluid being provided to the at least one additional fluid outlet;

a first multiplier, to receive the first signal and the second signal, multiply the first signal by the second signal to provide a first multiplied signal; and

a first flow controller, fluidly coupled to the fluid inlet and the first fluid outlet, to receive the first multiplied signal and provide the first predetermined portion of the amount of the process fluid to the first fluid outlet based upon the first multiplied signal;

wherein the first signal is based upon a pressure of the process fluid received at the fluid inlet.

17. A fluid flow controller to provide a flow of process fluid to a plurality of device inlets, comprising:

a fluid inlet to receive the flow of process fluid;

a plurality of fluid outlets to provide the flow of process fluid to the plurality of device inlets, the plurality of fluid outlets including a first fluid outlet and at least one additional fluid outlet;

a first input to receive a first signal indicative of an amount of the process fluid that is received at the fluid inlet;

a second input to receive a second signal indicative of a first predetermined portion of the amount of the process fluid that is to be provided to the first fluid outlet, with a remaining portion of the amount of the process fluid being provided to the at least one additional fluid outlet;

a first multiplier, to receive the first signal and the second signal, multiply the first signal by the second signal to provide a first multiplied signal; and

a first flow controller, fluidly coupled to the fluid inlet and the first fluid outlet, to receive the first multiplied signal and provide the first predetermined portion of the amount of the process fluid to the first fluid outlet based upon the first multiplied signal;

wherein the at least one additional fluid outlet includes a plurality of additional fluid outlets that together provide the remaining portion of the amount of the process fluid, the fluid flow controller further comprising;

a plurality of additional inputs each to receive a respective additional signal indicative of a respective second portion of the remaining portion of the amount of the process fluid to be respectively provided to each of the plurality of additional fluid outlets;

a plurality of second multipliers corresponding to each respective additional input, each to receive the first signal and the respective additional signal and multiply the first signal by the respective additional signal to provide a respective second multiplied signal; and

a plurality of second flow controllers corresponding to each respective second multiplier and fluidly coupled to the fluid inlet and a respective additional fluid outlet of the plurality of additional fluid outlets, each to receive the respective second multiplied signal from the corresponding second multiplier and provide the respective second portion of the remaining portion of the amount of process fluid to the respective additional fluid outlet based upon the respective second multiplied signal; and

wherein the first signal identifies a pressure of the process fluid received at the fluid inlet.

18. A fluid flow controller to provide a flow of process fluid to a plurality of device inlets, comprising:

a fluid inlet to receive the flow of process fluid;

a plurality of fluid outlets to provide the flow of process fluid to the plurality of device inlets, the plurality of fluid outlets including a first fluid outlet and at least one additional fluid outlet;

a first input to receive a first signal indicative of an amount of the process fluid that is received at the fluid inlet;

a second input to receive a second signal indicative of a first predetermined portion of the amount of the process fluid that is to be provided to the first fluid outlet, with a remaining portion of the amount of the process fluid being provided to the at least one additional fluid outlet;

a first multiplier, to receive the first signal and the second signal, multiply the first signal by the second signal to provide a first multiplied signal; and

a first flow controller, fluidly coupled to the fluid inlet and the first fluid outlet, to receive the first multiplied signal and provide the first predetermined portion of the amount of the process fluid to the first fluid outlet based upon the first multiplied signal;

wherein the at least one additional fluid outlet includes a plurality of additional fluid outlets that together provide the remaining portion of the amount of the process fluid, the fluid flow controller further comprising;

a plurality of additional inputs each to receive a respective additional signal indicative of a respective second portion of the remaining portion of the amount of the process fluid to be respectively provided to each of the plurality of additional fluid outlet;

a plurality of second multipliers corresponding to each respective additional input, each to receive the first signal and the respective additional signal and multiply the first signal by the respective additional signal to provide a respective second multiplied signal; and

a plurality of second flow controllers corresponding to each respective second multiplier and fluidly coupled to the fluid inlet and a respective additional fluid outlet of the plurality of additional fluid outlets, each to receive the respective second multiplied signal from the corresponding second multiplier and provide the respective second portion of the remaining portion of the amount of process fluid to the respective additional fluid outlet based upon the respective second multiplied signal; and

wherein the first signal is based upon a pressure of the process fluid received at the fluid inlet.

19. A fluid flow controller, comprising:

a first input to receive a first signal indicative of an amount of process fluid received at a fluid inlet;

a second input to receive a second signal indicative of a first predetermined portion of the received amount of the process fluid; and

a first multiplier, to receive the first signal and the second signal, multiply the first signal by the second signal, and provide a first multiplied signal indicative of the first predetermined portion of the amount of process fluid, independent of the amount of the process fluid received at the fluid inlet;

wherein the first signal identifies a pressure of the process fluid received at the fluid inlet.

20. A The fluid flow controller, comprising:

a first input to receive a first signal indicative of an amount of process fluid received at a fluid inlet;

a second input to receive a second signal indicative of a first predetermined portion of the received amount of the process fluid; and

a first multiplier, to receive the first signal and the second signal, multiply the first signal by the second signal, and provide a first multiplied signal indicative of the first predetermined portion of the amount of process fluid, independent of the amount of the process fluid received at the fluid inlet;

wherein the first signal is based upon a pressure of the process fluid received at the fluid inlet.

21. The fluid flow controller of claim 20, further comprising:

a plurality of additional inputs each to receive a respective additional signal indicative of a second predetermined portion of the amount of the process fluid received at the fluid inlet; and

a plurality of second multipliers corresponding to each respective additional input, each to receive the first signal and the respective additional signal, multiply the first signal by the respective additional signal, and provide a respective second multiplied signal indicative of each second predetermined portion of the amount of the process fluid, independent of the amount of the process fluid received at the fluid inlet.