| 摘要 |
<p>An Intrinsic Return Means (IRM) (21,22,23) may be imparted to a rotary or linear Shape Memory. Alloy actuator (SMA), thereby omitting the use of a spring return mechanism. The rotational actuator may include a cylindrical bobbin (30) with a helical groove (32,33) to receive an SMA wire (38,39). A number of turns may be placed in a small lengh of bobbin to amplify the rotational excursion. In another rotational actuator, a plurality of narrow, coaxial rings (51) are provided, the rings being nested in close concentric fit or stacked in side-by-side fashion. Each ring is provided with a groove (52) extending thereabout to receive an SMA wire (53). Contraction of the wire causes each causes ring to rotate with respect to the adjacent ring. In an embodiment for linear actuation, the invention provides a bar-like component (101) having SMA wires (113) joined between bars. The invention includes a lost motion coupling (221) to join two counter-acting SMA stroke amplification devices, whether linear or rotational.</p> |
