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US4671097A Expired / Lapsed US ⏱️ 0.0 years remaining

Calibration system for the calibration of mass flow controllers

Assignee: Nokia Oyj
•
Filing: 1985-06-14
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Granted: 1987-06-09
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Expires: 2005-06-14
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Abstract

Abstract A calibration system for the calibration of mass flow controllers of an apparatus used for a chemical vapor phase growth, comprising at least one mass flow meter for measuring the characteristics of the mass flow controllers and a computer for calculating correction coefficients for the different controllers. The system preferably comprises at least one flow meter for measuring at least the adjoining ranges of the mass flow controllers covering adjacent flow ranges.

Inventors

  • 👤 Jouko Kurki
  • 👤 Orjan Sandvik
  • 👤 Tiina Nyrkio-Maklin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 23:07
CPC Classifications
G; G05; G05D; G05D7/00; G05D7/06; G05D7/0617; G05D7/0629; G05D7/0635; G05D7/0641

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 88 words
In a calibration system for the calibration of mass flow controllers of an apparatus used for a chemical vapor phase growth, said system including mass flow meters for measuring the mass flows through said mass flow controllers, and means for calculating and storing correction coefficients for the different controllers whereby linear characteristics can be obtained for said controllers, the improvement wherein at least one of said mass flow meters occupies a measuring range covering at least adjoining ranges of two said mass flow controllers covering adjacent flow ranges.
Claim 2
Dependent Claim 88 words
In a calibration system for the calibration of mass flow controllers of an apparatus used for a chemical vapor phase growth, said system including mass flow meters for measuring the mass flows through said mass flow controllers, and means for calculating and storing correction coefficients for the different controllers whereby linear characteristics can be obtained for said controllers, the improvement wherein at least one of said mass flow meters occupies a measuring range covering at least adjoining ranges of two said mass flow controllers covering adjacent flow ranges.
Claim 3
Dependent Claim 35 words
The improvement claimed in claim 1, wherein at least two said mass flow meters occupy adjacent measuring ranges for obtaining a wider linear control range for said two mass flow controllers covering adjacent flow ranges.
Claim 4
Dependent Claim 28 words
The improvement claimed in claim 1, wherein at least some parts of said mass flow meters and said mass flow controllers are positioned on a common tempered base.

References Cited (Backward Citations)

US4096746A Cited
US4276243A Cited
GB2054204A Cited
US4341107A Cited
US4436674A Cited
US4566307A Cited
US4565092A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-06-08 1990-12-08 1991-06-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-06-08 1994-12-08 1995-06-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-06-08 1998-12-08 1999-06-09 $7700.00 Window Closed / Lapsed

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