Leakage current management systems, devices, and methods
AssigneeNxStage Medical, Inc.
InventorMark F. Smith
Life of this patent
Estimating the term…
Abstract
A sensor/transducer for use in reducing leakage current from a patient fluidly connected to a medical device by tubing filled with a conductive fluid (e.g., blood or dialysate (a “fluid line”)) includes a magnetically conductive core with 1) a centrally located support for a coil of fluid line, and 2) coiled electrical conductors located at positions that are spaced from the centrally located support, on opposite sides of the centrally located support. The sensor/transducer can be used to measure leakage current carried by the conductive fluid in the fluid line, or it can be used to induce current in the fluid line in a manner that reduces the leakage current.
Claims19
A device for detecting an electrical current flowing through a fluid line, the device comprising:
- a magnetically conductive core with a centrally located support member configured to receive a length of coiled conductor, and
- at least two electrically conducting coils located at positions that are spaced from the centrally located support member on opposite sides thereof, wherein
- the magnetically conductive core comprises a magnetically conductive central branch on which the centrally located support member is disposed in surrounding relationship and a pair of magnetically conductive outer branches with at least one of the electrically conducting coils disposed in surrounding relationship to each of the outer branches, and
- the centrally located support member comprises a spool which surrounds the magnetically conductive central branch.
A system for sensing and counteracting leakage current from a patient fluidly connected to a medical device by tubing filled with a conductive fluid, the system comprising:
- at least a pair of sensor/transducers, each of the sensor/transducers including
- a magnetically conductive core with a centrally located support member configured to receive a length of tubing filled with the conductive fluid, and
- at least two electrically conducting coils located at positions that are spaced from the centrally located support member on opposite sides thereof,
- wherein the magnetically conductive core comprises a magnetically conductive central branch on which the centrally located support member is disposed in surrounding relationship and a pair of magnetically conductive outer branches with at least one of the electrically conducting coils disposed in surrounding relationship to each of the outer branches, and
- wherein the magnetically conductive core forms two magnetic sub-circuits with the magnetically conductive central branch forming a common portion of each of the two magnetic sub-circuits and with each of the magnetically conductive outer branches forming a portion of one of the two magnetic sub-circuits,
- wherein said at least a pair of sensor/transducers are disposed on the tubing with the tubing supported by the centrally located support member and coiled around the magnetically conductive central branch of each sensor/transducer, with a first one of the sensor/transducers arranged to detect leakage current flowing within the conductive fluid and a second one of the sensor/transducers arranged to induce current within the conductive fluid to counteract the leakage current when voltage is applied to the electrically conducting coils of the second sensor/transducer.
Dependencies are inferred from the claim text.