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US4191952A Expired / Lapsed US ⏱️ 0.0 years remaining

Low oxygen flow alarm for anesthesia systems

Assignee: NAD Inc
•
Filing: 1978-08-25
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Granted: 1980-03-04
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Expires: 1998-08-25
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Abstract

Abstract In anesthesia apparatus for supplying oxygen and an anesthesia gas through respective flow control valves to a patient breathing circuit a low oxygen flow alarm system is provided. The alarm system includes a restrictor in the pipeline of the oxygen flow control valve and a restrictor in the pipeline of the anesthesia gas flow control valve. A differential pressure sensing unit including a diaphragm assembly responsive to the pressure in the oxygen pipeline and another diaphragm assembly responsive to the pressure in the anesthesia gas pipeline is coupled to the restrictor pipelines. The diaphragm assemblies are opposed to each other and coupled together by a displaceable linkage. Electrical switch means are provided coupled to the linkage to provide an alarm signal when the linkage has been moved to a predetermined position indicating that the oxygen concentration has dropped below a predetermined value. The differential pressure sensing unit includes spring biasing means.

Inventors

  • 👤 Peter J. Schreiber
  • 👤 Joachim G. M. Schreiber

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 17:34
CPC Classifications
G; G01; G01L; G01L19/00; G01L19/08; G01L19/12; A; A61; A61M; A61M16/00; A61M16/0051; A61M16/021; A61M16/08; A61M16/0816; A61M16/0841; A61M16/0858; A61M16/0003; A61M2016/0027

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 162 words
An alarm system for use with anesthesia apparatus supplying oxygen through one line into a manifold while supplying an anesthesia gas through a second line into the manifold, said alarm system comprising first pressure actuated means responsive to the oxygen pressure in said first line and having a first output member whose position is dependent upon said oxygen pressure, second pressure actuated means responsive to the anesthesia gas pressure in said second line and having a second output member whose position is dependent upon anesthesia gas pressure, and alarm means including displaceable means, said first and second output members being coupled to said displaceable means and acting in opposition therein, such that said first output means tends to move the displaceable means in a first direction while said second output means tends to move the displaceable means in a second direction, said alarm means producing an alarm signal wherever said displaceable means has been moved in said second direction to predetermined position.
Claim 2
Dependent Claim 162 words
An alarm system for use with anesthesia apparatus supplying oxygen through one line into a manifold while supplying an anesthesia gas through a second line into the manifold, said alarm system comprising first pressure actuated means responsive to the oxygen pressure in said first line and having a first output member whose position is dependent upon said oxygen pressure, second pressure actuated means responsive to the anesthesia gas pressure in said second line and having a second output member whose position is dependent upon anesthesia gas pressure, and alarm means including displaceable means, said first and second output members being coupled to said displaceable means and acting in opposition therein, such that said first output means tends to move the displaceable means in a first direction while said second output means tends to move the displaceable means in a second direction, said alarm means producing an alarm signal wherever said displaceable means has been moved in said second direction to predetermined position.
Claim 3
Dependent Claim 25 words
The alarm system of claim 1 wherein said first line includes a first restrictor therein and wherein said second line includes a second restrictor therein.
Claim 4
Dependent Claim 40 words
The alarm system of claim 2 wherein said first pressure actuated means comprises a first moveable diaphragm, said second pressure actuated means comprises a second moveable diaphragm and said displaceable means comprises linkage means interconnecting said first and second diaphragms.
Claim 5
Dependent Claim 19 words
The alarm system of claim 3 including fixed force biasing means acting in opposition to said first moveable diaphragm.
Claim 6
Dependent Claim 13 words
The alarm system of claim 4 wherein said biasing means comprises a spring.
Claim 7
Dependent Claim 19 words
The alarm system of claim 5 wherein said alarm system additionally comprises a switch located at said predetermined position.
Claim 8
Dependent Claim 29 words
The alarm system of claim 6 wherein said linkage means comprises adjustable stop arranged to actuate said switch when said linkage means has been moved to said predetermined position.
Claim 9
Dependent Claim 13 words
The alarm system of claim 7 wherein said switch is an electrical switch.
Claim 10
Dependent Claim 15 words
The alarm system of claim 8 additionally comprising illuminating means for producing said alarm signal.
Claim 11
Dependent Claim 11 words
The alarm system of claim 5 wherein said restrictors are linear.

References Cited (Backward Citations)

US3632924A Cited
US4148311A Cited
US4100537A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-03-04 1983-09-03 1984-03-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-03-04 1987-09-03 1988-03-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-03-04 1991-09-03 1992-03-04 $7700.00 Window Closed / Lapsed

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