Therapeutic gas flow meter and monitor

• US 5,911,219 A
• Filed: 04/18/1997
• Issued: 06/15/1999
• Est. Priority Date: 04/18/1997
• Status: Expired due to Fees

• Current Assignee: Alonzo C. Aylsworth, Charles Graham, Gregory R. Miller
• Original Assignee: Alonzo C. Aylsworth, Charles Graham, Gregory R. Miller
• Inventors: Graham, Charles, Aylsworth, Alonzo C., Miller, Gregory R.
• Primary Examiner(s): Weiss, John G.
• Assistant Examiner(s): Srivastava, V.
• Application Number:
  US08/839,799
• Time in Patent Office: 788 Days
• Field of Search: 128/205.23, 128/204.13, 128/204.14, 128/203.24, 128/205.24, 600/529, 73/861.55, 73/861.56, 73/861.57
• US Class Current: 128/205.23
• CPC Class Codes: A61M 16/101 using an oxygen concentrator
• CPC Class Codes: A61M 16/20 Valves specially adapted to medical respiratory devices
• CPC Class Codes: A61M 2202/0007 introduced into the body
• CPC Class Codes: A61M 2202/0208 Oxygen
• CPC Class Codes: A61M 2202/03 Gases in liquid phase, e.g. cryogenic liquids
• CPC Class Codes: A61M 2205/3553 remote, e.g. between patient's home and doctor's office
• CPC Class Codes: A61M 2205/3584 using modem, internet or bluetooth
• CPC Class Codes: G01F 1/22 by variable-area meters , e.g. rotameters

Abstract

A flow meter has a body, an inlet operatively connected to a source of gas, and an outlet. A valve for opening and closing the outlet is provided which includes a valve seat, a valve shaft movable axially relative to the valve seat and a valve member on the valve shaft. The valve member movable by axial translation of the valve shaft between a first position in which the valve member engages the valve seat to close the outlet and a second position in which the valve member is spaced from the valve seat to allow gas to pass through said outlet. The flow meter further includes a sensor which senses the position of said valve member relative to said valve seat and generates a signal indicative of said position. In one embodiment, the sensor comprises an infrared light emitter and an infrared photo-detector positioned on opposite sides of the valve member, which is preferably conical. Depending on the axial position of the valve member, the amount of light which reaches the photodetector changes. In another embodiment, the valve shaft is operable connected to a potentiometer which is responsive to the rotational position of the valve shaft, and hence the axial position of the valve member. In a third embodiment, a magnet is placed about the valve shaft, and a magnetic field detector is placed within the magnets magnetic field. The sensor is responsive to the position of the magnet and hence the position of the valve member.

Claims

1. A flow meter having a body, an inlet operatively connected to a source of gas, an outlet, and a valve for opening and closing the outlet, the valve including a valve seat, valve shaft movable axially relative to said outlet and a valve member provided on said valve shaft, said valve member movable between a first position in which said valve member engages said valve seat to close said outlet and a second position in which said valve member is spaced from said valve seat to allow gas to pass through said outlet;

said flow meter further including a sensor which senses the position of said valve member relative to said valve seat and generates a signal indicative of said position;

said sensor comprising a potentiometer having a rotatable shaft, said valve shaft being coupled to said potentiometer shaft such that said valve shaft will translate axially without moving said potentiometer, said potentiometer generating a signal indicative of the rotational position of said valve shaft, and hence of the setting of the valve member.

2. A flow meter having a body, an inlet operatively connected to a source of gas, an outlet, and a valve for opening and closing the outlet, the valve including a valve seat, valve shaft movable axially relative to said outlet and a valve member provided on said valve shaft, said valve member movable between a first position in which said valve member engages said valve seat to close said outlet and a second position in which said valve member is spaced from said valve seat to allow gas to pass through said outlet;

said flow meter further including a sensor which senses the position of said valve member relative to said valve seat and generates a signal indicative of said position;

said sensor comprising an annular magnet fixed to said valve shaft at a desired axial location along said valve shaft and a magnetorestrictive sensor;

said magnet producing a magnetic field, said magnetorestrictive sensor being positioned externally of said flow meter and within said magnetic field, said magnetorestrictive sensor generating an output indicative of the strength of said magnetic field for a specified location in the setting of the said shaft, wherein, when said valve shaft and valve member translate axially, the position of the magnet, and hence the magnetic field, move relative to magnetorestrictive sensor, the signal generated by the magnetorestrictive sensor being indicative of the setting of the position of the valve shaft, and hence the valve member.

3. A flow meter having a body, an inlet operatively connected to a source of gas, an outlet, and a valve for opening and closing the outlet, the valve including a valve seat, valve shaft movable axially relative to said outlet and a valve member provided on said valve shaft, said valve member movable between a first position in which said valve member engages said valve seat to close said outlet, and a second position in which said valve member is spaced from said valve seat to allow gas to pass through said outlet, said flow meter further including a sensor which senses the position of said valve member relative to said valve seat and generates a signal indicative of said position;

said sensor comprising an emitter which produces an infrared light beam and photo detector which detects infrared light, said emitter and detector being positioned in said meter on opposite sides of said valve member, such that said detector can detect light transmitted perpendicularly across said valve member by said emitter, said valve member having a tapered surface such that as said valve shaft, and hence said valve member translate axially relative to said valve seat, the quantity of light emitted by said emitter which reaches said detector varies, said detector generating an output signal indicative of the amount of light which impinges on said detector, and provides an indication of the position of said valve member;

a microprocessor including a data storage device, said microprocessor being operatively connected to said sensor to receive said signal generated by the sensor, said microprocessor including means for converting said signal from said sensor into information indicative of the setting of the flow meter valve shaft through passage of the infrared light beam perpendicularly there across, and wherein said microprocessor stores the information in said storage device.

4. The flow meter of claim 3 wherein said microprocessor includes a comparator and an alarm, said microprocessor storing prescription information in said data storage device, said comparator comparing said setting of the flow meter against said prescription information;

said comparator generating a signal if said information does not correspond to said prescription information, said alarm being responsive to said comparator signal to activate said alarm when said setting information does not correspond to said prescription information.

5. The flow meter of claim 4 herein said microprocessor includes communication means, said communication means being operable to transmit the information store in the data storage device to a remote location.