Extended life SMA actuator
US5419788A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 1993 |
| Grant date | May 30, 1995 |
| Priority date | — |
| Expiry date | Dec 10, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S420/902
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention relates to a method for increasing the useful life of a shape memory alloy (SMA) actuator, wherein the SMA element contracts on heating and elongates on cooling under an applied stress and that property is used as an actuating technique. More specifically, the present invention relates to the cooling aspect of the cycle and maintaining a martensite strain on the actuator SMA element at less than about 3% by limiting the upper stress on the element. In the most preferred embodiment, the element is a ribbon actuator prepared from a nickel-titanium SMA alloy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.