Patent · US Expired

Extended life SMA actuator

US5419788A · kind A · utility

21Cited by
10References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 10, 1993
Grant dateMay 30, 1995
Priority date
Expiry dateDec 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.