Fluid delivery apparatus with shape-memory flow control element
US4645489A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1985 |
| Grant date | Feb 24, 1987 |
| Priority date | — |
| Expiry date | Apr 29, 2005 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M5/16813
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A unitary disposable conduit extends from the intravenous reservoir along a gravity-flow path to the patient, and incorporates a valve block containing an externally controlled flow-control valve. An electronic controller monitors the drop rate in a drop chamber which is an integral part of the disposable conduit, compares this rate with an operator-selected rate, and controls the valve by varying the current in a shape-memory actuator element whose movements, caused by the resultant Joule heating, are coupled to the valve to proportionally vary the flow rate in the conduit. The valve block is securely received within a recess in the controller, and is automatically coupled to the controller when inserted within this recess. The shape-memory actuator element may be incorporated within the disposable valve block, or may form a part of the controller, with a simple mechanical coupling to transmit its movements to the valve. The valve may be automatically or manually closed when the valve block is removed from the controller, or if power failure occurs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.