Dual electromagnet partially disposable fluid flow transducer with side-by-side electrodes

• US 5,417,119 A
• Filed: 01/07/1994
• Issued: 05/23/1995
• Est. Priority Date: 01/07/1994
• Status: Expired due to Fees

• Current Assignee: Owen C. Smoll
• Original Assignee: Owen C. Smoll
• Inventors: Smoll, Owen C.
• Primary Examiner(s): Chilcot, Jr., Richard E.
• Assistant Examiner(s): Dougherty, Elizabeth L.
• Application Number:
  US08/178,562
• Time in Patent Office: 501 Days
• Field of Search: 73/861.08, 73/861.11, 73/861.12, 73/861.15-861.17, 128/691
• US Class Current: 73/861.12
• CPC Class Codes: A61M 1/3663 Flow rate transducers; Flow integrators
• CPC Class Codes: G01F 1/58 by electromagnetic flowmeters
• CPC Class Codes: G01F 1/584 constructions of electrodes, accessories therefor
• CPC Class Codes: G01F 1/586 constructions of coils, magnetic circuits, accessories therefor G01F1/582 takes precedence; magnet; inductances; transformers; selection of materials for their magnetic properties per se H01F
• CPC Class Codes: G01F 15/18 Supports or connecting means for meters

Abstract

An electromagnetic flow meter for measuring the flow of conductive fluids, e.g. blood, in an extracorporeal circuit. The electromagnetic flow meter utilizes two electromagnets positioned in a portion of the housing of a transducer unit, and a disposable insert easily insertable into a cavity of the housing. The electromagnets generate, at any one time, magnetic fields having opposite directions. The conductive fluid flows in a direction perpendicular to the direction of the magnetic fields for inducing first and second voltages. First and second electrodes extend into the bore of the disposable insert and provide the voltages, generated by the fluid flow cutting through the magnetic fields, to first and second pick-up sockets in said housing.

Claims

1. An electromagnetic flow meter for measuring blood flow, comprising:

transducer means having a blocked "C" shaped housing, said transducer means comprising a first electromagnet with a winding wrapped around said first electromagnet in a first direction, a second electromagnet with said winding wrapped around said second electromagnet in a second direction, said winding for receiving a driving signal, a first pick-up socket and a second pick-up socket; and

insert means for insertion into an extracorporeal circuit comprising a rectangular central section having a constant tubular bore, said central section being insertable into a cavity of said transducer means, a first electrode and a second electrode extending into said tubular bore of said central section for contacting said blood, said first electrode and said second electrode being spaced apart from each other on one side of said central section along the same diametrical plane, said first and second electrodes extending radially outward from said one side of said central section for forming first and second connectors for insertion into said first and second pick-up sockets, respectively;

said insert means having first and second end portions each having a conical shape for enabling said insert means to be inserted into said extracorporeal circuit, said first and second end portions each having a constant tubular bore diametrically equal to the constant tubular bore of said central section for enabling said blood to flow unimpaired through said insert means.

2. The electromagnetic flow meter as set forth in claim 1, said insert means further comprising a key formed on a side orthogonal to the one side from which said first and second electrodes extend.

3. The electromagnetic flow meter as set forth in claim 1, said first and second electromagnets being positioned over said cavity of said transducer means for generating magnetic fields having opposite directions of flow perpendicular to the flow of said blood flowing through said insert means, in response to said driving signal.

4. The electromagnetic flow meter as set forth in claim 3, said first electrode for providing a first voltage to said first pick-up socket in response to said blood flowing perpendicular to said magnetic field produced by said first electromagnet.

5. The electromagnetic flow meter as set forth in claim 3, said second electrode for providing a second voltage to said second pick-up socket in response to said blood flowing perpendicular to said magnetic field produced by said second electromagnet.

6. The electromagnetic flow meter as set forth in claim 3, said first electrode for providing a first voltage to said first pick-up socket in response to said blood flowing perpendicular to said magnetic field produced by said first electromagnet, and said second electrode for providing a second voltage to said second pick-up socket in response to said blood flowing perpendicular to said magnetic field produced by said second electromagnet.

7. A disposable insert for an electromagnetic flow meter having a transducer unit formed by a blocked "C" shaped housing, said transducer unit comprising a first electromagnet with a winding wrapped around a core of said first electromagnet in a first direction, a second electromagnet with said winding wrapped around a core of said second electromagnet in a second direction, said winding receiving a driving signal, and said housing having a first pick-up socket and a second pick-up socket, electromagnetic flow meter measuring fluid flow of a conductive fluid, said disposable insert comprising:

a rectangular central section having a tubular bore of constant diameter, said central section being insertable into a cavity of said blocked "C" shaped housing;

a first electrode and a second electrode extending into said tubular bore of said central section for contacting said conductive fluid, said first electrode and said second electrode being spaced apart from each other on one side of said central section along the same diametrical plane, said first and second electrodes extending radially outward from said one side of said central section for forming first and second connectors for insertion into said first and second pick-up sockets, respectively; and

first and second end portions each having a conical shape for enabling said insert to be inserted into an extracorporeal circuit, said first and second end portions each having a constant tubular bore diametrically equal to the constant diameter of said tubular bore of said central section for enabling said conductive fluid to flow unimpaired through said insert means.

8. The disposable insert as claimed in claim 7, further comprising a key formed on a side orthogonal to the one side from which said first and second electrodes extend for ensuring said disposable insert is inserted into said cavity in a predetermined manner.

9. The disposable insert as claimed in claim 7, further comprising said first electrode providing a first voltage to said first pick-up socket in response to said conductive fluid flowing perpendicular to a first magnetic field produced by said first electromagnet, and said second electrode providing a second voltage to said second pick-up socket in response to said conductive fluid flowing perpendicular to a second magnetic field produced by said second magnet, a direction of flow for said first magnetic field being opposite to a direction of flow for said second magnetic field.

10. An electromagnetic flow meter comprising a transducer and a disposable insert for measuring blood flow in an extracorporeal circuit, said transducer comprising:

a blocked "C" shaped magnet housing having a cavity in which said disposable insert is to be inserted;

a first electromagnet with a winding wrapped around a first core in a first direction;

a second electromagnet with said winding wrapped around a second core in a second direction opposite said first direction;

said winding receiving a driving signal for enabling said first electromagnet to generate a first magnetic field and for enabling said second electromagnet to generate a second electromagnetic field, a direction of flow for said first magnetic field being opposite to a direction of flow for said second magnetic field;

said first and second electromagnets being positioned in an upper portion of said blocked "C" shaped housing over said cavity;

a first pick-up socket; and

a second pick-up socket;

said first and second sockets extending from a central portion of said blocked "C" shaped magnet housing.

11. The electromagnetic flow meter as set forth in claim 10, said disposable insert comprising:

a rectangular central section having a tubular bore of constant diameter, said central section being insertable into said cavity of said blocked "C" shaped housing;

a first electrode and a second electrode extending into said tubular bore of said central section for contacting said blood, said first electrode and said second electrode being spaced apart from each other on a same side of said central section along the same diametrical plane, said first and second electrodes extending radially outward from said one side of said central section for forming first and second connectors for insertion into said first and second pick-up sockets, respectively; and

first and second end portions each having a conical shape for enabling said disposable insert to be inserted into said extracorporeal circuit, said first and second end portions each having a constant tubular bore diametrically equal to the constant diameter of said tubular bore of said central section for enabling said blood to flow unimpaired through said insert means.

12. The electromagnetic flow meter as set forth in claim 11, said disposable insert further comprising one key formed on at least one side of said central section, said at least one side being orthogonal to the side from which said first and second electrodes extend for ensuring said disposable insert is inserted into said cavity in a predetermined manner.

13. The electromagnetic flow meter as set forth in claim 11, said disposable insert further comprising said first electrode providing a first voltage to said first pick-up socket in response to said blood flowing perpendicular to said first magnetic field produced by said first electromagnet, and said second electrode providing a second voltage to said second pick-up socket in response to said blood flowing perpendicular to said second magnetic field produced by said second magnet.