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US4432761A Expired / Lapsed US ⏱️ 0.0 years remaining

Volumetric drop detector

Assignee: Abbott Laboratories
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Filing: 1982-09-24
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Granted: 1984-02-21
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Expires: 2002-09-24
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Abstract

Abstract A device for measuring the volume of flow in a liquid conveying apparatus wherein the length and velocity of a liquid column are measured. Drops of the liquid are formed and directed into a length of measurement tubing having a known internal diameter. As the liquid column is passed through the measurement tubing its length is determined by two spaced apart liquid sensors. The actual length is determined by calculating the time elapsed for the leading edge of the liquid column to interrupt the two liquid sensors. The time for the trailing edge to pass the first sensor is proportioned to the length of the column and the quotient of the two values will give the actual length. Accordingly, accurate volume determinations can be made irrespective of velocity change such as due to viscosity, surface tension or back pressure. The device of this invention is especially adapted to be used in conjunction with an intravenous administration set.

Inventors

  • 👤 Garfield A. Dawe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:38
CPC Classifications
G; G01; G01F; G01F3/00; A; A61; A61M; A61M5/00; A61M5/14; A61M5/168; A61M5/16886; A61M5/1689

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 126 words
A volumetric measuring device for use with a liquid conveying apparatus including the usual first and second flow paths comprising: liquid drop forming means; a length of measurement tubing having a known internal diameter; means operatively associated with said drop forming means to direct liquid drops into said measurement tubing to form a liquid column; first and second liquid sensor means operatively positioned with respect to said measurement tubing; electronic means operatively associated with said first and second liquid sensor means to measure the velocity and length of said liquid column; collecting means positioned from said measurement tubing to receive said measured drops; and connector means operatively associated with said drop forming means and said collecting means for connection with said first and second flow paths.
Claim 2
Dependent Claim 126 words
A volumetric measuring device for use with a liquid conveying apparatus including the usual first and second flow paths comprising: liquid drop forming means; a length of measurement tubing having a known internal diameter; means operatively associated with said drop forming means to direct liquid drops into said measurement tubing to form a liquid column; first and second liquid sensor means operatively positioned with respect to said measurement tubing; electronic means operatively associated with said first and second liquid sensor means to measure the velocity and length of said liquid column; collecting means positioned from said measurement tubing to receive said measured drops; and connector means operatively associated with said drop forming means and said collecting means for connection with said first and second flow paths.
Claim 3
Dependent Claim 22 words
The volumetric measuring device as defined in claim 1 wherein said first and second liquid sensor means are of the optoelectronic type.
Claim 4
Dependent Claim 29 words
The volumetric measuring device as defined in claim 2 wherein said electronic means includes timing means to measure the leading edge of said drop twice and trailing edge once.
Claim 5
Dependent Claim 31 words
The volumetric measuring device as defined in claim 1 wherein said means to direct liquid drops into said measurement tubing is defined by a funnel portion connected to said measurement tubing.
Claim 6
Dependent Claim 31 words
The volumetric measuring device as defined in claim 4 wherein said collecting means is defined by a chamber and said measurement tubing provides a drop discharging means at the end thereof.
Claim 7
Dependent Claim 63 words
The volumetric measuring device as defined in claim 5 further including a tubular housing member positioned to surround said measurement tubing and said funnel member, said tubular housing in fluid tight engagement with said collecting means at one end and said connector means for said drop forming means at the other, said drop forming means and said tubular housing defining a drip chamber.
Claim 8
Dependent Claim 39 words
The volumetric measuring device as defined in claim 6 wherein said collecting means is defined by a chamber member further including a centering sleeve operatively contacting said measurement tubing and said tubular housing as well as said chamber member.
Claim 9
Dependent Claim 41 words
The volumetric measuring device as defined in claim 6 further including a liquid container connection means secured to said first flow path opposite said drip chamber and an intravenous delivery device secured to said second flow path opposite said chamber member.
Claim 10
Dependent Claim 140 words
A volumetric measuring device for use with an intravenous administration apparatus including the usual first and second lengths of flexible tubing comprising: liquid drop forming means; a length of measurement tubing having a known internal diameter; means operatively associated with said drop forming means to direct liquid drops into said measurement tubing to form a liquid column; first and second liquid sensor means including two pairs of operatively positioned drop length sensors operatively positioned with respect to said measurement tubing; electronic means operatively associated with said first and second liquid sensor means to measure the velocity and length of said liquid column; collecting means positioned from said measurement tubing to receive said measured drops; and tubing connector means operatively associated with said drop forming means and said collecting means for connection with said first and second lengths of flexible tubing.
Claim 11
Dependent Claim 140 words
A volumetric measuring device for use with an intravenous administration apparatus including the usual first and second lengths of flexible tubing comprising: liquid drop forming means; a length of measurement tubing having a known internal diameter; means operatively associated with said drop forming means to direct liquid drops into said measurement tubing to form a liquid column; first and second liquid sensor means including two pairs of operatively positioned drop length sensors operatively positioned with respect to said measurement tubing; electronic means operatively associated with said first and second liquid sensor means to measure the velocity and length of said liquid column; collecting means positioned from said measurement tubing to receive said measured drops; and tubing connector means operatively associated with said drop forming means and said collecting means for connection with said first and second lengths of flexible tubing.
Claim 12
Dependent Claim 60 words
The volumetric measuring device as defined in claim 9 wherein said optoelectronic means further includes: a first timer; a second timer; an oscillator; a divider for said first and second timer; a summer divider; and a totalizer; said timers, oscillator, dividers and totalizer all operatively connected to provide a digital readout of the total volume delivered of said liquid columns.
Claim 13
Dependent Claim 29 words
The volumetric measuring device as defined in claim 10 further including a rate divider operatively connected to said summer divider to provide a digital readout of the delivery rate.
Claim 14
Dependent Claim 20 words
The volumetric measuring device as defined in claim 11 wherein said measurement tubing is composed of a polypropylene resin material.
Claim 15
Dependent Claim 28 words
The volumetric measuring device as defined in claim 12 wherein said measurement tubing has an internal diameter in the range of about 1 mm to about 5 mm.
Claim 16
Dependent Claim 124 words
A disposable device for monitoring or controlling liquid flow having first and second flow paths, said device for use with an optoelectronic device having at least two spaced apart electronic means to determine the length of a drop of liquid flowing therein comprising: liquid forming means; a length of measurement tubing having a known internal diameter and a length of sufficient dimension to accommodate said electronic means when positioned in oppositely disposed pairs; means operatively associated with said drop forming means to direct liquid drops into said measurement tubing; collecting means positioned from said measurement tubing to receive said measured drops; and connector means operatively associated with said drop forming means and said collecting means for connection with said first and second flow paths.
Claim 17
Dependent Claim 124 words
A disposable device for monitoring or controlling liquid flow having first and second flow paths, said device for use with an optoelectronic device having at least two spaced apart electronic means to determine the length of a drop of liquid flowing therein comprising: liquid forming means; a length of measurement tubing having a known internal diameter and a length of sufficient dimension to accommodate said electronic means when positioned in oppositely disposed pairs; means operatively associated with said drop forming means to direct liquid drops into said measurement tubing; collecting means positioned from said measurement tubing to receive said measured drops; and connector means operatively associated with said drop forming means and said collecting means for connection with said first and second flow paths.
Claim 18
Dependent Claim 30 words
The disposable device as defined in claim 14 wherein said means to direct liquid drops into said measurement tubing is defined by a funnel portion connected to said measurement tubing.
Claim 19
Dependent Claim 43 words
The disposable device as defined in claim 15 wherein said disposable device forms a part of a disposable I.V. administration set and said collecting means is defined by a chamber and said measurement tubing provides a drop discharging means at the end thereof.
Claim 20
Dependent Claim 64 words
The disposable I.V. administration set as defined in claim 16 further including a tubular housing member positioned to surround said measurement tubing and said funnel member, said tubular housing in fluid tight engagement with said collecting means at one end and said connector means for said drop forming means at the other, said drop forming means and said tubular housing defining a drip chamber.
Claim 21
Dependent Claim 41 words
The disposable I.V. administration set as defined in claim 17 wherein said collecting means is defined by a chamber member and further including a centering sleeve operatively contacting said measurement tubing and said tubular housing as well as said chamber member.
Claim 22
Dependent Claim 42 words
The disposable I.V. administration set as defined in claim 18 further including a liquid container connection means secured to said first flow path opposite said drip chamber and an intravenous delivery device secured to said second flow path opposite said collecting means.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-02-20 1987-08-22 1988-02-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-02-20 1991-08-22 1992-02-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-02-20 1995-08-22 1996-02-21 $7700.00 Window Closed / Lapsed

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