Syringe plunger position detection and alarm generation
US5236416A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 1991 |
| Grant date | Aug 17, 1993 |
| Priority date | — |
| Expiry date | May 23, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S128/01
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A syringe plunger position detection and alarm system continuously determines the position of a syringe plunger and provides near end of travel and end of travel alarms. Plunger movement is also monitored and if movement is less than a calculated amount, an alarm is provided. A variety of syringes of different sizes is usable. A potentiometer is mounted along the line of travel of the screw drive mechanism and a marker is mounted to extend from the screw mechanism to the potentiometer to force an internal contact in the potentiometer. The voltage provided by this internal contact is analyzed by the process to derive absolute and relative position of the plunger. The end of travel position of each plunger is stored in processor memory and from the operator input rate of infusion, the characteristic curve of the potentiometer also stored in memory, the plunger displacement of the syringe, and the time of the near end of travel alarm, the voltage of the near end of travel position is calculated. The potentiometer is self-contained and sealed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.