Apparatus for mass flow measurement of a gas

Patent 5684245 Issued on November 4, 1997. Estimated Expiration Date:

November 17, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3668554

3729995

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Inventor

Hinkle, Luke D.

Application

No. 560037 filed on 11/17/1995

US Classes:

73/1.35, With pressure measurement or plural flowmeters73/861.02, Electrical73/865MASS

Examiners

Primary: Noland, Tom

Attorney, Agent or Firm

Lappin & Kusmer LLP

International Classes

G01F 025/00
G01F 001/50
G01F 001/86

Abstract

Apparatus for and method of measuring mass flow of a gas in a gas delivery system. The apparatus is adapted to be connected to a source of a gas. The apparatus includes a fixed-volume chamber in fluid connection with the gas source. A flow control device can be used to control the flow of the gas into the chamber. A transducer assembly comprises, in combination, a pressure transducer in fluid connection with the chamber, and a signal modifying network associated with the pressure transducer. The pressure transducer permits measurement of the pressure of the gas in the chamber and provides a first electrical signal representative of the pressure of the known volume of the gas. The signal modifying network modifies the first signal to produce an output signal which is proportional to PV/RT and thus directly represents the number of moles of the gas in the chamber. The apparatus is useful for calibrating mass flow controllers and the like.

Other References

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