Pulsed drop detector for intravenous systems
US5267978A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 29, 1990 |
| Grant date | Dec 7, 1993 |
| Priority date | — |
| Expiry date | Aug 29, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S128/13
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A drop detector for intravenous systems in which an infrared emitter is pulsed at 10 kHz. The pulsed radiation passes through a drip chamber and then to a detector. The detector circuit determines the amplitude modulation of the 10 kHz. carrier frequency. This provides an indication of when the drop falling through the drip chamber has interrupted the light beam. An automatic gain control circuit maintains the output of the detector, on a long time constant basis, at a constant level to eliminate the vagaries of drip chambers with different optical characteristics and the like. When the AGC circuit lacks the ability to maintain the output of the detector circuitry at a constant level, a fault detector provides an alarm to indicate that the circuitry has exceeded its operational range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.