Fluid delivery control and monitoring apparatus for a medication infusion system
US4919596A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1989 |
| Grant date | Apr 24, 1990 |
| Priority date | — |
| Expiry date | Apr 26, 2009 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M5/16827
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A fluid delivery monitoring and control apparatus for use in a medication infusion system is designed for use with a disposable fluid pathway that incorporates a sterile cassette containing pumping elements and sensor interfaces. The apparatus comprises a multi-segment drive mechanism, controller, and monitoring system. Fluid pumping is accomplished by controlling DC motors in the drive mechanism, each of which is coupled to two valves and a reciprocating piston for an individual pumping channel in the cassette. The motor is geared down to provide an appropriate maximum speed and torque. A cam sequentially actuates an inlet valve, piston, and an outlet valve in the cassette. A range of fluid delivery rates is achieved by periodically sending pulses to the motor. The output flow rate of the pump is maintained by a digital feedback controller which uses closed-loop feedback control to provide accurate regulation. At regular time intervals, the controller computes the motor voltage pulse width based upon feedback information from an encoder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.