Electrical sensor for fluids

• US 10,406,269 B2
• Filed: 12/29/2015
• Issued: 09/10/2019
• Est. Priority Date: 12/29/2015
• Status: Active Grant

• Current Assignee: Fresenius Medical Care Holdings Incorporated (Fresenius Medical Care AG)
• Original Assignee: Fresenius Medical Care Holdings Incorporated (Fresenius Medical Care AG)
• Inventors: Weaver, Colin, Alber, Elliott, James, Philip Scott, Schmidt, Daniel
• Primary Examiner(s): Gurtowski, Richard C
• Application Number:
  US14/982,805
• Publication Number:
  US 20170182235A1
• Time in Patent Office: 1,351 Days
• Field of Search: None
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/1607 before use, i.e. upstream of dialyser
• CPC Class Codes: A61M 1/1609 after use, i.e. downstream of dialyser
• CPC Class Codes: A61M 1/1656 Apparatus for preparing dialysates
• CPC Class Codes: A61M 1/1664 with temperature control
• CPC Class Codes: A61M 1/1696 with dialysate regeneration
• CPC Class Codes: A61M 2205/0227 Materials having sensing or indicating function, e.g. indicating a pressure increase
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3331 Pressure; Flow
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/60 with identification means
• CPC Class Codes: G01N 27/07 Construction of measuring vessels; Electrodes therefor

Abstract

An electrical sensor for sensing electromagnetic properties of process fluids in a dialysis machine or a similar medical device can include a probe for interfacing with the fluids that is made from electronic fabric materials. The electronic fabric probe can include one or more conductors embedded in a non-conductive fabric layer. The electronic fabric probe is accommodated an enclosure which establishes a flow path with respect to the probe to establish fluid contact between the process fluids and the conductors. The conductors can apply or sense current and/or voltage with respect to the fluid. A portion of the electronic fabric probe can be disposed externally of the enclosure to provide electronic communication externally of the enclosure.

Claims

1. An electrical sensor for a medical machine, wherein the electrical sensor comprises:

an electronic fabric probe having a non-conductive fabric layer and a plurality of conductors including a first conductor and a second conductor embedded in the fabric layer, the first conductor and the second conductor being spaced apart from each other and including a respective first terminal and a second terminal exposed proximate a peripheral edge of the fabric layer; and

an enclosure enclosing a fluid chamber delineating a flow path for fluid between a fluid inlet and a fluid outlet, the enclosure adapted to accommodate the electronic fabric probe with the first and second conductors disposed in the flow path and arranged to electrically communicate with each other via the fluid to sense an electrical characteristic of the fluid and with the first and second terminals accessible outside the enclosure;

wherein the electrical sensor has a flow-over configuration with a fluid inlet disposed at an entry region of the fluid chamber and a fluid outlet disposed at an exit region of the fluid chamber, and the fluid inlet and the fluid outlet are directed toward a same surface of the fabric layer;

wherein the fluid chamber has an oblong shape with the entry region disposed at a first end and the exit region disposed at a second end;

wherein the electronic fabric probe is received in a depression disposed in a planar surface of the enclosure to maintain a planar configuration of the electronic fabric probe.

2. The electrical sensor of claim 1, wherein the fabric layer is a non-conductive mesh and the first and second conductors are formed as conductive threads embedded in the mesh.

3. The electrical sensor of claim 2, wherein the electronic fabric probe is selected from the group consisting of a two-conductor configuration, a three-conductor configuration, and a four-conductor configuration.

4. The electrical sensor of claim 3, wherein the electrical sensor measures conductivity of the fluid.

5. The electrical sensor of claim 4, further comprising an electrical connector for connecting the first terminal and the second terminal to an electronic controller associated with the medical machine.

6. The electrical sensor of claim 1, wherein the fluid inlet and the fluid outlet are configured as hose fittings enabling the electrical sensor to be removed from the medical machine.

7. The electrical sensor of claim 6, wherein the enclosure is made of molded plastic and includes a first enclosure portion and a second enclosure portion that can be disassembled to access the fluid chamber and remove and replace the electronic fabric probe.

14. The electrical sensor of claim 1, wherein the electronic fabric probe is removable from the enclosure of the electrical sensor for replacement by another electronic fabric probe within the enclosure of the electrical sensor.

15. The electrical sensor of claim 1, further comprising one or more additional electronic fabric probes configured for determining a flow rate of the fluid.

16. The electrical sensor of claim 15, wherein the one or more additional electronic fabric probes include a heating probe and two thermal sensing probes, wherein the heating probe is disposed between the two thermal sensing probes.

8. A dialysis machine comprising:

a dialyzer delineating a dialysate side and a blood side separated by a membrane;

a fluid source for supplying fluid in a liquid phase;

at least one fluid line communicating the fluid to the dialyzer;

a pump disposed in the at least one fluid line for directing fluid to and from the dialyzer;

an electrical sensor disposed in the at least one fluid line, the electrical sensor including an electronic fabric probe accommodated in an enclosure enclosing a fluid chamber having a fluid inlet and a fluid outlet coupled to the at least one fluid line, the electronic fabric probe having a non-conductive fabric layer with a first conductor and a second conductor embedded in the fabric layer, the first and second conductors disposed in a flow path delineated by the enclosure and spaced apart from each other, and

an electronic controller electrically connected to the electrical sensor and in electronic communication with the first conductor and the second conductor, the electronic controller operatively associated with a human-machine interface for displaying information about the fluid determined by electrical communication between the first conductor and the second conductor via the fluid;

wherein the electrical sensor has a flow-over configuration with the fluid inlet disposed at an entry region of the fluid chamber and the fluid outlet disposed at an exit region of the fluid chamber, and the fluid inlet and the fluid outlet are directed toward a same surface of the fabric layer;

wherein the fluid chamber has an oblong shape with the entry region disposed at a first end and the exit region disposed at a second end;

wherein the electronic fabric probe is received in a depression disposed in a planar surface of the enclosure to maintain a planar configuration of the electronic fabric probe.

9. The dialysis machine of claim 8, wherein the first conductor and the second conductor are spaced apart a predetermined distance on the fabric layer.

10. The dialysis machine of claim 9, wherein the first and second conductors are excitation electrodes configured to cause a current to be conducted through the fluid.

11. The dialysis machine of claim 10, wherein the controller is operatively associated with a meter to determine a voltage drop between third and fourth conductors of the electronic fabric probe.

12. The dialysis machine of claim 8, wherein the electrical sensor is disposable with the fluid inlet and the fluid outlet configured as hose fittings for releasable connection to the at least one fluid line.

13. A method of measuring conductivity of a fluid flowing in a dialysis machine during dialysis treatment, the method comprising:

connecting an electrical sensor to an electronic controller operatively associated with the dialysis machine, the electrical sensor including an electronic fabric probe accommodated in a fluid chamber delineated by an enclosure of the electrical sensor;

directing the fluid into the fluid chamber through a fluid inlet of the enclosure;

applying current or voltage to the fluid in the fluid chamber via a first conductor embedded in a fabric layer of the electronic fabric probe;

sensing the conductivity of the fluid in the fluid chamber via a second conductor disposed in the fabric layer of the electronic fabric probe and spaced apart from the first conductor; and

discarding the electronic fabric probe after the dialysis treatment;

wherein the electrical sensor has a flow-over configuration with the fluid inlet disposed at an entry region of the fluid chamber and a fluid outlet disposed at an exit region of the fluid chamber, and the fluid inlet and the fluid outlet are directed toward a same surface of the fabric layer;

wherein the fluid chamber has an oblong shape with the entry region disposed at a first end and the exit region disposed at a second end;

wherein the electronic fabric probe is received in a depression disposed in a planar surface of the enclosure to maintain a planar configuration of the electronic fabric probe.