Treatment Fluid Devices Methods and Systems

Patent metadata

Field	Value
Publication number	US-2020155747-A1
Application number	US-201916712385-A
Country	US
Kind code	A1
Filing date	Dec 12, 2019
Priority date	Oct 30, 2015
Publication date	May 21, 2020
Grant date	—

Abstract

A conductivity measurement device includes first and second conductivity measurement flow channels positioned in a fluid circuit and fluidly linked for fluid flow between the first and second conductivity measurement flow channels. A controller having a current source connected to the first and second conductivity channels applies alternating voltages at frequencies that are different, each being respective to one of the first and second conductivity cells.

First claim

What is claimed is:

1 . A conductivity measurement device, comprising:
a first conductivity measurement flow channel; a second conductivity measurement flow channel, the first and second conductivity flow channels positioned in a fluid circuit and fluidly linked for fluid flow between the first and second conductivity measurement flow channels; and a controller having a current source connected to the first and second conductivity measurement flow channels, the controller being configured to apply alternating voltages at frequencies that are different, each frequency being respective to one of the first and second conductivity measurement flow channels.

2 . The device of claim 1 , wherein the controller is configured to measure voltage drops across respective channels of the first and second conductivity measurement flow channels.

3 . The device of claim 1 , wherein the respective frequency applied to the first conductivity measurement flow channel is between 1.2 and 5 times the respective frequency applied to the second conductivity measurement flow channel.

4 . The device of claim 1 , wherein the respective frequency applied to the first conductivity measurement flow channel is selected to prevent interference in measurement of voltage drop with the frequency applied to the second conductivity measurement flow channel.

5 . The device of claim 1 , wherein
the frequency applied to the first conductivity measurement flow channel is substantially greater than the frequency applied to the second conductivity measurement flow channel, the controller is configured to measure voltage drops across respective channels of the first and second conductivity measurement flow channels, and the controller is configured to demodulate the voltage drops by low-pass-filtering the voltage drops.

6 . The device of claim 5 , wherein
a cutoff frequency of a filter used by the controller for the low pass filtering is at least the respective frequency applied to the second conductivity measurement flow channel

7 . A medicament delivery system, comprising:
a fluid circuit attached to a pump and a controller; the fluid circuit having multiple conductivity measurement portions, each having a pair of electrodes; the controller being connected to the pairs of electrodes and configured to generate a current between each pair of the electrodes cyclically at different times so a current exists between only the pair of electrodes of one of the multiple conductivity measurement portions at a given time.

8 . The system of claim 7 , wherein the current is an alternating current.

9 . The system of claim 7 , wherein the current between each pair of electrodes is maintained for a fraction of a second.

10 . A medicament delivery system, comprising:
a pump actuator adapted to receive a predefined fluid circuit and a controller; the fluid circuit having multiple conductivity measurement portions, each having a pair of electrodes; the controller being connectable to the pairs of electrodes and configured to generate a current between each pair cyclically at different times so a current exists between only one of each pair at a given time.

11 . The system of claim 10 , wherein the current is an alternating current.

12 . The system of claim 10 , wherein the current between each pair is maintained for a fraction of a second.

Assignees

• Nxstage Medical Inc

Inventors

• Soto Orlando
• Rausa Joseph
• Brugger James M
• Schnell William J
• Friederichs Goetz
• Burbank Jeffrey H
• Turk Jr Joseph E
• Newell Scott W
• Wozniak Amanda

Classifications

• A61M2205/3317

  Electromagnetic, inductive or dielectric measuring means · CPC title

• A61M2205/12

  with interchangeable cassettes forming partially or totally the fluid circuit · CPC title

• A61M5/14228

  with linear peristaltic action, i.e. comprising at least three pressurising members or a helical member · CPC title

• A61M2205/3368

  Temperature · CPC title

• A61M1/1668 Primary

  Details of containers · CPC title