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US3890968A Expired / Lapsed US ⏱️ 0.0 years remaining

Fluid flow control means

Assignee: Sanmina Corp
•
Filing: 1971-06-25
•
Granted: 1975-06-24
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Expires: 1991-06-25
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Abstract

Abstract The flow controller repeatedly opens and closes a magnetic check valve for periods of time which determine the flow rate through the valve. The magnetic valve preferably has a movable valve closure member with an elongated stem which extends parallel to the direction of flow of fluid through the check valve. The stem is made of magnetic material. An electro-magnet is placed at the side of the valve, outside of the valve housing. The electromagnetic field pulls the valve stem laterally to tip the valve member and open the valve. When the magnet is de-energized, the valve member moves back to its seat. The controller is used to control the flow of parenteral fluids into the veins of a human patient. The parenteral fluid controller has a drip chamber for collecting drops of fluid falling from a reservoir. The magnetic check valve is located in the conduit between the drip chamber and the patient''s vein. A drop detector is provided for producing a signal each time a drop is formed. The latter signal controls the opening and closing of the valve and thus controls the flow of the parenteral fluid. Safety features are provided whereby the valve closes automatically if a drop has not been detected for a pre-determined length of time. Therefore, abnormalities in the operation of the system will not cause excessive flow of Fluid or infusion of air into the patient''s veins. An attendant will be warned of such a condition, or if the flow rate is too low or too high, or if the fluid level in the reservoir is low.

Inventors

  • 👤 Oscar L Pierce
  • 👤 Arthur H Hutchison
  • 👤 Olin B King
  • 👤 Lonnie S Mcmillian

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 21:14
CPC Classifications
A; A61; A61M; A61M5/00; A61M5/14; A61M5/168; A61M5/16831; A61M5/1684; A61M5/16886; A61M5/1689; A61M2205/00; A61M2205/18; A61M2205/33; A61M2205/3317; A61M2205/3379; A61M2205/3386; A61M5/1411; Y; Y10; Y10S; Y10S128/00; Y10S128/13; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7758; Y10T137/7759

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 110 words
A parenteral fluid flow controller comprising, in combination, closed conduit means for conveying said fluid to a patient, flow control valve means including a magnetic check valve enclosed within said conduit for controlling the flow of said fluid to said patient, actuating means including magnetic means outside of said conduit for repeatedly actuating said valve means to permit flow therethrough in increments, drop formation means for forming drops of said fluid from a fluid reservoir, and control means for making the time duration of opening of said valve means inversely proportional to the time rate of formation of said drops at substantially all times during the operation of said controller.
Claim 2
Dependent Claim 110 words
A parenteral fluid flow controller comprising, in combination, closed conduit means for conveying said fluid to a patient, flow control valve means including a magnetic check valve enclosed within said conduit for controlling the flow of said fluid to said patient, actuating means including magnetic means outside of said conduit for repeatedly actuating said valve means to permit flow therethrough in increments, drop formation means for forming drops of said fluid from a fluid reservoir, and control means for making the time duration of opening of said valve means inversely proportional to the time rate of formation of said drops at substantially all times during the operation of said controller.
Claim 3
Dependent Claim 25 words
A controller as in claim 1 including means for making the frequency of actuation of said valve means substantially greater than the drop formation frequency.
Claim 4
Dependent Claim 48 words
A controller as in claim 1 including time delay means for disabling said actuating means in response to a pre-determined time delay in the formation of a drop, said delay being at least equal to the time required to form a plurality of drops at a pre-determined frequency.
Claim 5
Dependent Claim 46 words
A controller as in claim 1 including means for comparing the drop formation frequency with a pre-determined frequency and developing an alarm signal in response to the detection of a drop formation frequency which is different from said pre-determined frequency by more than a pre-determined amount.
Claim 6
Dependent Claim 73 words
A controller as in claim 1 including means for detecting the reservoir level of said fluid and producing an alarm signal in response to the detection of a level below a pre-determined value, and means for reducing the duration of opening of said valve to a fixed minimum level in response to said alarm signal, and for closing said valve indefinitely when no drop has been formed for a pre-determined length of time.
Claim 7
Dependent Claim 123 words
A parenteral fluid flow controller as in claim 1 in which said magnetic check valve includes a housing, a valve seat in said housing, a movable valve member in said housing, said valve member having a portion of magnetic material, a barrier member positioned adjacent said seat and said valve member to limit the lateral travel of said valve member away from said seat and maintain said valve member in a position, at its point of laterally furthest travel, in which the flow of fluid through said valve urges said valve member towards said seat, and magnetic force-creating means for creating a lateral magnetic force for moving said valve member towards said barrier member and away from said seat to open said valve.
Claim 8
Dependent Claim 49 words
A controller as in claim 1 in which said magnetic check valve includes a valve member with at least a portion made of magnetic material, said magnetic means outside of said conduit including tipping means for tipping and thereby unseating said valve member by means of a magnetic field.
Claim 9
Dependent Claim 47 words
A controller as in claim 7 in which said check valve includes a valve seat in said conduit, said valve member having a transverse closure portion and an axially-extending stem of magnetic material, said tipping means including a magnet positioned adjacent said stem outside said conveying means.
Claim 10
Dependent Claim 33 words
A controller as in claim 1 in which said actuating means includes an oscillator, and means for setting tHe frequency of said oscillator to correspond to changes in the size of said drops.
Claim 11
Dependent Claim 37 words
A controller as in claim 1 including irrigation means for automatically opening and closing said valve means when no drop has been detected for a pre-determined length of time to maintain a minimum level of fluid flow.
Claim 12
Dependent Claim 29 words
A controller as in claim 10 including means for disabling said irrigation means in response to the absence of a drop detection for a further pre-determined length of time.
Claim 13
Dependent Claim 80 words
A controller as in claim 1 including drop detection means for forming a drop signal corresponding to each of said drops, signal generating means for generating a rate signal whose magnitude varies with respect to time at a predetermined rate, level detector means for detecting the magnitude of said rate signal and actuating said valve means when said magnitude crosses a pre-determined level, and starting means responsive to said drop signal for restoring said rate signal to a starting level.
Claim 14
Dependent Claim 24 words
A controller as in claim 12 including means to vary said rate in order to vary the rate of fluid flow through said conduit.
Claim 15
Dependent Claim 22 words
A controller as in claim 12 in which said starting means is adapted to restore said rate signal by a fixed amount.
Claim 16
Dependent Claim 114 words
A parenteral fluid flow controller comprising means for forming drops of said fluid, a conduit means for conducting fluid from said drop forming means to a patient, drop detecting means for detecting said drops, valve means for regulating the flow through said conduit means, means for opening said valve means, means for automatically closing said valve means when the time between successive drop detections exceeds a pre-determined value, means for developing a signal whenever the automatic closing means operates, means for accumulating said signals over a length of time, and means for gradually introducing said signals into the controller system so as to compensate for the flow lost and maintain an even flow rate.
Claim 17
Dependent Claim 114 words
A parenteral fluid flow controller comprising means for forming drops of said fluid, a conduit means for conducting fluid from said drop forming means to a patient, drop detecting means for detecting said drops, valve means for regulating the flow through said conduit means, means for opening said valve means, means for automatically closing said valve means when the time between successive drop detections exceeds a pre-determined value, means for developing a signal whenever the automatic closing means operates, means for accumulating said signals over a length of time, and means for gradually introducing said signals into the controller system so as to compensate for the flow lost and maintain an even flow rate.
Claim 18
Dependent Claim 116 words
In a parenteral fluid administration device, means for forming drops of fluid, means for conducting fluid from said drop forming means to a patient, drop detector means for developing an electrical signal in response to detection of a drop, said drop detector means having first electrode means for contacting said fluid upstream from the position at which said drop is formed, and second electrode means positioned at a distance below said drop formation position such that a drop forming at said position will contact said second electrode only after it has started to decrease in diameter at its base to separate from said upstream fluid, but before said drop is completely separated from said upstream fluid.
Claim 19
Dependent Claim 116 words
In a parenteral fluid administration device, means for forming drops of fluid, means for conducting fluid from said drop forming means to a patient, drop detector means for developing an electrical signal in response to detection of a drop, said drop detector means having first electrode means for contacting said fluid upstream from the position at which said drop is formed, and second electrode means positioned at a distance below said drop formation position such that a drop forming at said position will contact said second electrode only after it has started to decrease in diameter at its base to separate from said upstream fluid, but before said drop is completely separated from said upstream fluid.

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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) 1978-06-23 1978-12-23 1979-06-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-06-23 1982-12-23 1983-06-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-06-23 1986-12-23 1987-06-24 $7700.00 Window Closed / Lapsed

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