Tracking and controlling fluid delivery from chamber
US9222819B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 2012 |
| Grant date | Dec 29, 2015 |
| Priority date | — |
| Expiry date | May 14, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M3/40
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Electrochemical impedance may be used for accurate and real-time tracking and control of fluid delivery from fluid-filled chambers, such as from drug delivery devices. At least two measurement electrodes may be placed within the chamber in contact with the fluid to be sensed. Application of a small alternating current using these electrodes through the fluid/drug may allow measurement of electrochemical impedance. Volumetric changes of the compressible chamber due to movement of at least one surface within the compressible chamber (such as an actuating bellows or flexible diaphragm), may induce changes in the measured electrochemical impedance. Measuring these changes may allow for tracking of ejected liquid volumes from the compressible chamber. By taking the time-derivative of this signal, the rate of volume change can be tracked and therefore the rate of ejected fluid (flow rate) can be deduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.