Granted Patent B2

US 8,131,400 · App. 12/797,753 · Granted Mar 6, 2012

Abstract

Claims (62)

1. A method of providing mass flow controller flow rate data for a non-manufacturing-tuning-gas comprising,

operating the mass flow controller with the non-manufacturing-tuning-gas at a setpoint greater than 50%;

recording data from the mass flow controller in a mass flow controller memory;

changing the setpoint to 0%;

analyzing the recorded data;

calculating one or more non-manufacturing-tuning-gas correction algorithm parameters;

storing the one or more non-manufacturing-tuning-gas correction algorithm parameters in a mass flow controller memory; and

using the one or more non-manufacturing-tuning-gas correction algorithm parameters in at least one future mass flow controller operation involving the non-manufacturing-tuning-gas.

2. The method of claim 1 wherein, the steps of, recording data from the mass flow controller in a mass flow controller memory, analyzing the recorded data, calculating one or more non-manufacturing-tuning-gas correction algorithm parameters, storing the one or more non-manufacturing-tuning-gas correction algorithm parameters in a mass flow controller memory, and using the one or more non-manufacturing-tuning-gas correction algorithm parameters in at least one future mass flow controller operation involving the non-manufacturing-tuning-gas are automatically performed by the mass flow controller.

3. The method of claim 2 wherein, the steps of, recording data from the mass flow controller in a mass flow controller memory, analyzing the recorded data, calculating one or more non-manufacturing-tuning-gas correction algorithm parameters, storing the one or more non-manufacturing-tuning-gas correction algorithm parameters in a mass flow controller memory, and using the one or more non-manufacturing-tuning-gas correction algorithm parameters in at least one future mass flow controller operation involving the non-manufacturing-tuning-gas are performed by the mass flow controller transparent to a mass flow controller user.

4. The method of claim 1 wherein, the steps of, recording data from the mass flow controller in a mass flow controller memory, analyzing the recorded data, calculating one or more non-manufacturing-tuning-gas correction algorithm parameters, and storing the one or more non-manufacturing-tuning-gas correction algorithm parameters in a mass flow controller memory are performed by the mass flow controller while the mass flow controller is in an idle mode.

5. The method of claim 1 wherein, the steps of analyzing the recorded data and calculating one or more non-manufacturing-tuning-gas correction algorithm parameters are performed by a mass flow controller firmware.

6. The method of claim 5 wherein, the data is recorded at a fastest data recordation speed allowed by the mass flow controller.

7. The method of claim 6 wherein, the fastest data recordation speed allowed by the mass flow controller comprises recording at least one data point for every mass flow controller firmware loop cycle.

8. The method of claim 1 wherein, the recorded data comprises at least 100 data samples.

9. The method of claim 1 wherein, analyzing the recorded data comprises at least one of,

comparing the recorded data with a separate dataset and determining that the mass flow controller is not operating properly; and

comparing newly calculated gas-specific correction algorithm parameters with previously calculated gas-specific correction algorithm parameters and determining if the difference between the two parameter values exceeds some specified threshold.

10. A method of providing accurate mass flow controller flow rate data for a non-manufacturing-tuning-gas comprising,

one of setting the mass flow controller to a zero setpoint and setting the valve to a zero position while the mass flow controller is in a valve override control mode;

changing the input pressure;

producing a parasitic flow within the mass flow controller;

measuring mass flow controller flow rate data and pressure data;

storing the mass flow controller flow rate data and pressure data in a mass flow controller memory;

analyzing the flow rate data and the pressure data;

calculating one or more non-manufacturing-tuning-gas correction algorithm parameters;

storing the one or more non-manufacturing-tuning-gas correction algorithm parameters in a mass flow controller memory; and

using the one or more non-manufacturing-tuning-gas correction algorithm parameters in at least one future mass flow controller operation involving the non-manufacturing-tuning-gas.

11. The method of claim 10 wherein, the parasitic flow comprises at least a 5% controller full scale flow.

12. The method of claim 10 wherein, the input pressure is changed through at least one of a pressure spike and a non-temporary pressure change.

13. The method of claim 10 wherein, at least one of the pressure data and flow rate data is overwritten with at least one of subsequent pressure data and flow rate data if an input pressure change is not detected within a specified range.

14. The method of claim 10 wherein, at least one of the pressure data and flow rate data is overwritten with at least one of subsequent pressure data and flow rate data if an adjusted flow rate is not outside of a specified flow rate range.

15. The method of claim 10 , further comprising,

determining that an adjusted flow rate is outside of a specified flow rate range; and wherein,

calculating one or more non-manufacturing-tuning-gas correction algorithm parameters comprises using the pressure data and flow rate data to one of,

calculate new non-manufacturing-tuning-gas correction algorithm parameters, and

adjust current manufacturing-tuning-gas correction algorithm parameters.

16. The method of claim 10 wherein, the pressure is changed by an amount adapted to create a measurable flow rate reading outside a flow rate reading threshold.

17. A method of providing accurate mass flow controller flow rate data for a non-manufacturing-tuning-gas comprising,

operating the mass flow controller with the non-manufacturing-tuning-gas at a setpoint greater than 50%;

recording flow rate data from the mass flow controller in a mass flow controller memory;

recording pressure data from the mass flow controller in a mass flow controller memory;

changing the setpoint to 0%;

changing the input pressure;

producing a parasitic flow within the mass flow controller;

analyzing the recorded data with a correction algorithm;

calculating one or more non-manufacturing-tuning-gas parameters;

storing the one or more non-manufacturing-tuning-gas parameters in a mass flow controller memory; and

using the one or more non-manufacturing-tuning-gas parameters in at least one future mass flow controller operation involving the non-manufacturing-tuning-gas.

18. A mass flow controller adapted to receive a fluid other than the fluid used to determine correction algorithm parameters comprising,

a main flow line;

a thermal sensor operatively coupled to the main flow line;

a pressure sensor operatively coupled to the main flow line;

a control valve operatively coupled to the main flow line;

a memory device;

a digital controller electrically coupled to the memory device, operatively coupled to the control valve, and adapted to,

receive pressure data from the pressure sensor,

receive flow rate data the thermal sensor,

analyze the pressure data and flow rate data;

calculate one or more gas-specific parameters for an algorithm adapted to be applied to the flow rate data when at least one of,

a flow rate setpoint is changed from greater than 50% to 0%, and

a mass flow controller pressure fluctuates when the setpoint comprises 0%.

Assignments (8)