Apparatus and method for mass flow controller with on-line diagnostics

• US 20030234045A1
• Filed: 06/24/2002
• Published: 12/25/2003
• Est. Priority Date: 06/24/2002
• Status: Abandoned Application

• Current Assignee: MKS Instruments Incorporated
• Original Assignee: MKS Instruments Incorporated
• Inventors: Shajii, Ali, Ambrosina, Jesse, Kottenstette, Nicholas
• Application Number:
  US10/178,288
• Publication Number:
  US 20030234045A1
• Time in Patent Office: Days
• US Class Current: 137/487.5
• CPC Class Codes: G01F 1/684 Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
• CPC Class Codes: G01F 1/6965 comprising means to store calibration data for flow signal calculation or correction
• CPC Class Codes: G01F 1/86 Indirect mass flowmeters, e.g. measuring volume flow and density, temperature or pressure
• CPC Class Codes: G01F 25/15 specially adapted for gas meters G01F25/11 - G01F25/14, G01F25/17 take precedence
• CPC Class Codes: G01F 5/00 Measuring a proportion of the volume flow
• CPC Class Codes: G05D 7/0635 by action on throttling means G05D7/0688, G05D7/0694 take precedence
• CPC Class Codes: Y10T 137/7761 Electrically actuated valve

Abstract

A mass flow controller includes an interface and control for executing diagnostics while the mass flow controller'"'"'s electronic controller executes closed loop process control.

Claims

1. A mass flow controller comprising:

a mass flow sensor configured to produce a mass flow signal representative of a gas flow through the mass flow controller; and

an electronic controller configured to produce a closed loop control signal for an outlet valve, based on said mass flow signal, wherein said electronic controller is also configured to provide an interface for on-line diagnostics.

2. The mass flow controller of claim 1 wherein said electronic controller is configured to provide a network interface that permits the execution of mass flow controller active diagnostics.

3. The mass flow controller of claim 2 wherein active diagnostics code operational with the mass flow controller'"'"'s electronic controller includes code to enable the manipulation of operational signals.

4. The mass flow controller of claim 2 wherein active diagnostics code operational with the mass flow controller'"'"'s electronic controller includes code to enable the manipulation of diagnostic signals.

5. The mass flow controller of claim 2 wherein active diagnostics code operational with the mass flow controller'"'"'s electronic controller includes code to enable the monitoring of operational signals.

6. The mass flow controller of claim 2 wherein active diagnostics code operational with the mass flow controller'"'"'s electronic controller includes code to enable the monitoring of diagnostic signals.

7. The mass flow controller of claim 2 further wherein on-line diagnostics code operational with the mass flow controller'"'"'s electronic controller enables on-line monitoring of operational signals.

8. The mass flow controller of claim 2 wherein on-line diagnostics code operational with the mass flow controller'"'"'s electronic controller enables on-line monitoring of diagnostic signals.

9. The mass flow controller of claim 2 wherein on-line diagnostics code operational with the mass flow controller'"'"'s electronic controller enables on-line manipulation of diagnostic signals.

10. The mass flow controller of claim 2 wherein on-line diagnostics code operational with the mass flow controller'"'"'s electronic controller enables on-line manipulation of operational signals.

11. A mass flow controller comprising:

a mass flow sensor configured to produce a mass flow signal representative of a gas flow through the mass flow controller;

an electronic controller configured to produce a closed loop control signal for an outlet valve based on said mass flow signal, wherein said electronic controller comprises a dual-processor controller that is configured to provide an interface for on-line diagnostics.

12. The mass flow controller of claim 11 wherein active diagnostics code operational with the mass flow controller'"'"'s electronic controller includes code to enable the manipulation of operational mass flow controller signals.

13. The mass flow controller of claim 11 wherein active diagnostics code operational with the mass flow controller'"'"'s electronic controller includes code to enable the manipulation of diagnostic mass flow controller signals.

14. The mass flow controller of claim 11 wherein active diagnostics code operational with the mass flow controller'"'"'s electronic controller includes code to enable the monitoring of operational mass flow controller signals.

15. The mass flow controller of claim 11 wherein active diagnostics code operational with the mass flow controller'"'"'s electronic controller includes code to enable the monitoring of diagnostic mass flow controller signals.

16. The mass flow controller of claim 11 wherein said dual processors include a processor configured to operate in a deterministic mode and a processor configured to operate in a non-deterministic mode and the deterministic processor is configured to produce said closed loop control signal for an outlet valve.

17. The mass flow controller of claim 16 wherein the deterministic processor is configured to acquire one or more sensor readings.

18. The mass flow controller of claim 17 wherein the mass flow sensor is a thermal mass flow sensor, including a sensor bypass, configured to sense the flow of fluid into the inlet of the controller and the mass flow controller further comprises a pressures sensor configured to sense the fluid pressure in the volume between the thermal mass flow sensor bypass and the control valve, and said deterministic processor is configured to acquire a pressure signal produced by said pressure sensor and to compensate the sensed inlet flow rate sensed by said mass flow sensor using the pressure signal to thereby produce a compensated measure of the rate of fluid flow out of the controller.

19. The mass flow controller of claim 18 wherein the deterministic processor is configured to compute the time rate of change of pressure within the volume between the sensor bypass and the outlet control valve, and to use this time rate of change of pressure to produce the compensated measure of the rate of fluid flow out of the controller.

20. The mass flow controller of claim 11 wherein the network interface comprises a web server that enables a web-enabled device connected to the world wide web to execute on-line diagnostics from the web-enabled device.

21. The mass flow controller of claim 11 wherein the mass flow controller is self-calibrating.